Level III Whole Number Operations Bridging Unit (Pilot Materials) NSSAL (Draft) C. David Pilmer 2013 (Last Updated: October, 2013) NSSAL ©2013 i Draft C. D. Pilmer This resource is the intellectual property of the Adult Education Division of the Nova Scotia Department of Labour and Advanced Education. The following are permitted to use and reproduce this resource for classroom purposes. Nova Scotia instructors delivering the Nova Scotia Adult Learning Program Canadian public school teachers delivering public school curriculum Canadian non-profit tuition-free adult basic education programs The following are not permitted to use or reproduce this resource without the written authorization of the Adult Education Division of the Nova Scotia Department of Labour and Advanced Education. Upgrading programs at post-secondary institutions Core programs at post-secondary institutions Public or private schools outside of Canada Basic adult education programs outside of Canada Individuals, not including teachers or instructors, are permitted to use this resource for their own learning. They are not permitted to make multiple copies of the resource for distribution. Nor are they permitted to use this resource under the direction of a teacher or instructor at a learning institution. Acknowledgments The Adult Education Division would like to thank Dr. Genevieve Boulet (MSVU) for reviewing this resource and providing valuable feedback. The Adult Education Division would also like to thank the following ALP instructors for piloting this resource and offering suggestions during its development. Eileen Burchill (IT Campus) Elliott Churchill (Waterfront Campus) Lynn Cuzner (Marconi Campus) Carissa Dulong (Truro Campus) Krys Galvin (Truro Campus) Barbara Gillis (Burridge Campus) Nancy Harvey (Akerley Campus) Barbara Leck (Pictou Campus) Suzette Lowe (Lunenburg Campus) Alice Veenema (Kingstec Campus) NSSAL ©2013 ii Draft C. D. Pilmer Table of Contents Introduction (for Instructors) ……………………………………………………………… iii Introduction to Whole Number …………………………………………………………… Math Facts: Addition and Multiplication …………………………………………………. Fact Families ………………………………………………………………………………. Order of Operations ……………………………………………………………………….. Multiples of Ten, One Hundred, and One Thousand ……………………………………… Divisibility and Prime ……………………………………………………………………… Estimating …………………………………………………………………………………. Adding Multi-Digit Numbers ……………………………………………………………… Subtracting Multi-Digit Numbers …………………………………………………………. Multiplying Multi-Digit Numbers …………………………………………………………. Dividing Multi-Digit Numbers …………………………………………………………….. 1 7 17 22 26 33 35 38 41 45 53 Appendix ………………………………………………………………………………….. Connect Four Games …………………………………………………………………… Flash Cards …………………………………………………………………………….. Answers ………………………………………………………………………………… 61 62 71 85 NSSAL ©2013 iii Draft C. D. Pilmer Introduction (for Instructors) This unit is concerned with having learners: 1. Develop strong mental math skills as they pertain to the addition, subtraction, multiplication, and division facts associated with whole numbers. This means learners should develop a high level of automaticity associated these math facts. 2. Add, subtract, multiply, and divide multi-digit whole numbers, not limited to the traditional algorithms. They are also expected to use their estimation skills to judge the reasonableness of their final answer. Let's take a few minutes to discuss the importance of mental math. Mental math is the process of calculating the exact numerical answer without the aid of any external calculating or recording device. Research shows that as adults over 80% of the mathematics we encounter in our daily lives involves the mental manipulation of numerical quantities rather than the traditional paper and pencil math so often stressed in schools. Most learners feel that mental math is important however, they mistakenly believe that written math is learned in school while mental math is learned outside of school. Although learners may value mental math, they may not be able to perform even the most straightforward calculations mentally. Consider that on the Third National Mathematics Assessment, only 45% of 17 year olds were able to multiple 90 and 70 mentally. Research states that mental math activities should be integrated into daily classroom practices, rather than being taught as an isolated unit. The exposure should be gradual and continuous. For the Level III Math program, we recommend that such activities serve as a 4 to 6 minute warm-up at the beginning of a session for the first few weeks. There are three reasons for this approach. The first is that mental math is pervasive in the real-world and the curriculum. The continued classroom exposure to mental math is meant to be reflective of the math that learners encounter in the real-world and in the curriculum. The second reason deals with the memory demands of mental math. Mental math tends to be easier for individuals whose addition and multiplication facts are firmly entrenched in their long-term memory. If this is so, the working memory is available to work flexibility with number and operations. For learners who have not retained the addition and multiplication facts in their long-term memory, mental math can be very challenging. In these cases, their working memory is consumed with determining the fact, and they have little time or space left to address the question that was asked. When such memory deficits occur, we, as instructors, need to present the learners with a series of strategies that allow quick retrieval of pertinent facts. This goes beyond asking learners to go back and memorize addition and multiplication charts. Many adult learners have been unsuccessful with this approach, so more innovative strategies are required; strategies that are less taxing on the longterm memory. Consider the following examples. (1) Flip Flop (actually the commutative property) Many learners struggle with 9 3 because they attempt to figure out 9 sets of 3, however, if they know 9 3 3 9 , then the question is more accessible to some. Using the NSSAL ©2013 iv Draft C. D. Pilmer commutative property cuts the long-term memory requirements for the addition and multiplication tables almost in half. (2) Next Even/Next Odd When you add 2 to a whole number you just have to find the next even or odd number depending on the number you start with. If you start with an even number and add 2, then the sum is the next even number. If you start with an odd number and add 2, then the sum is the next odd number. (3) Add Ten, Then Subtract One This strategy is used when adding 9 to a number (e.g. 9 6 ). This strategy relies on the fact that most people are comfortable adding 10 to a number (e.g. 10 3 13 , 7 10 17 ). So if we want to add 9 and 4 (i.e. 9 4 ), we will add 10 and 4, then compensate by subtracting 1 (i.e. 10 4 1). (4) Double Double Multiplying a number by 4 is the same as doubling the number and then doubling that new answer. If you have 4 6 , then you double 6 and then double that answer. (5) Snake Legs People often confuse the rule for multiplying by 0 with the rule for adding 0. For the question 5 0 or 0 5 , learners need to remember that these mean 5 sets of 0, or 0 sets of 5. In either case, the answer is 0. The easiest way to remember this is to use the snake leg strategy. How many legs does one snake have? (Answer: 0) How many legs do five snakes? (Again the answer is 0). Therefore, we can conclude that 5 0 0 . Although these strategies, and the others that you will be exposed to in second section of this resource, reduce the demands on the long-term memory, many learners will still require time and practice to solidify the strategies in their long-term memory. If this is accomplished then learners can develop a higher level of automaticity. It should be mentioned that not all Level III learners will need to learn these strategies. A significant group of these individuals will recall these facts with a quick review/refresher of the addition and multiplication tables. However, there are other individuals who have repeatedly struggled to retain these facts through memorization; these strategies are designed for those individuals. Although all of these strategies only appear in one section of this resource, do not feel that most learners will master all their facts using all these strategies in a few lessons. It will likely take the learner several weeks to retain the strategies and the accompanying facts. As stressed earlier in this introduction, the exposure to these strategies should be both gradual and continuous. For further information on these strategies, and others, you may wish to access the Mental Math resource (found on SharePoint). As mentioned at the beginning of this introduction, we also want learners to be able to add, subtract, multiply, and divide multi-digit whole numbers, but not necessarily limiting them to the traditional algorithms. For example, there are learners who struggle to remember all the steps for NSSAL ©2013 v Draft C. D. Pilmer multiplying multi-digit whole numbers. For these individuals, they may prefer multiplying such numbers by multiplying them in their expanded forms. An example of this is shown below. e.g. 84 57 Answer: 80 4 50 7 2 5 6 2 0 4 0 0 8 0 0 0 The 7 must be multiplied by both the 80 and the 4. The 50 must be multiplied by both the 80 and the 4. 4 7 8 8 Does that mean that everyone must learn this alternate method? No; only those who are not best served by the traditional algorithm. NSSAL ©2013 vi Draft C. D. Pilmer Introduction to Whole Numbers The set of whole numbers is 0, 1, 2, 3, 4, 5,… (This set goes on indefinitely.) Whole numbers do not include: 2 9 and , (which are both between the whole numbers 0 and 1). 5 10 fractions like mixed numbers like 2 decimals like 0.09 (which is between the whole numbers 0 and 1) and 4.7 (which is between the whole numbers 4 and 5). negative numbers like -2 or -9.2 (which are both less than the whole number 0). 1 5 (which is between the whole numbers 2 and 3) and 7 (which 6 16 is between the whole numbers 7 and 8). For large whole numbers, we separate the digits into groups of three, called periods. Each period has a name: ones, thousands, millions, billions, and trillions. 3 480 120 000 ones thousands millions billions In Canada, we use spaces to separate the periods. In the United States, they use commas to separate the periods. We choose to use spaces because in Europe, those countries use the comma in the same way we and the US use a decimal point. Canada 2 649 705 830 3 834 000 United States 2,649 705,830 3,834,000 For this course, we are not really concerned with whether you use spaces or commas; just recognize that all Canadian math print resources will use spaces. Writing Numbers Using Words Many two digit numbers, like 46 and 73, are written using a hyphen. For example, the number 38 is written as thirty-eight. Similarly, the number 95 is written as ninety-five. The three-digit number 627 is written as six hundred twenty-seven. The most common mistake is writing it as six hundred and twenty-seven. The word "and" is not used when writing whole NSSAL ©2013 1 Draft C. D. Pilmer numbers using words. Rather, it is used with decimals and mixed numbers. For example, the 1 decimal 2.1 or the mixed number 2 is correctly written as two and one-tenth. 10 When writing larger whole numbers (i.e. four or more digits), it is important to know and understand the chart below. Example 1 Write each number in words. (a) 23 735 (c) 6 207 500 (e) 3 190 700 000 Ones Tens Ones Period Hundreds Thousands Ten Thousands Thousands Period Hundred Thousands Millions Ten Millions Hundred Millions Billions Ten Billions Hundred Billions Billions Period Trillions Ten Trillions Hundred Trillions Trillions Period Place Value Chart Millions Period (b) 270 516 (d) 15 049 670 (f) 56 000 987 000 Answers: When writing out your answers using words, separate each period using commas. Ironically we do not do this in Canada when writing the number in numerical form. (a) 23 735 twenty-three thousand, seven hundred thirty-five (b) 270 516 two hundred seventy thousand, five hundred sixteen (c) 6 207 500 six million, two hundred seven thousand, five hundred (d) 15 049 670 fifteen million, forty-nine thousand, six hundred seventy (e) 3 192 700 000 (f) 56 000 987 000 three billion, one hundred ninety-two million, seven hundred thousand fifty-six billion, nine hundred eighty-seven thousand Example 2 Give the place value of each underlined digit in each whole number. (a) 5 976 050 (b) 7 398 050 000 Answers: (a) 5 976 050 (b) 7 398 050 000 NSSAL ©2013 The 7 is in the ten thousands place. The 3 is in the hundred millions place. 2 Draft C. D. Pilmer Example 3 Write each number in expanded form. (a) 359 (c) 65 078 (e) 304 609 (b) 2 895 (d) 157 800 (f) 4 081 540 Answers: (a) 359 300 50 9 (b) 2 895 2 000 800 90 5 (c) 65 078 60 000 5 000 70 8 (d) 157 800 100 000 50 000 7 000 800 (e) 304 609 300 000 4 000 600 9 (f) 4 081 540 4 000 000 80 000 1 000 500 40 Questions 1. Write each number in words (a) 986 (b) 412 (c) 2 397 (d) 4 609 (e) 12 750 (f) 347 052 (g) 506 900 (h) 2 870 040 (i) 350 026 000 (j) 17 509 100 (k) 7 360 800 000 (l) 11 094 300 002 (m) 6 532 000 000 080 NSSAL ©2013 3 Draft C. D. Pilmer 2. Write each number using digits (a) six thousand, seven hundred forty-two (b) three million, one hundred twenty-six thousand, five hundred eleven (c) eight hundred nine thousand, three hundred twenty-seven (d) thirteen million, fifty-two thousand, seventy-one (e) sixty-three thousand, one hundred forty-seven (f) four hundred eight million, seven hundred thousand, two hundred sixty (g) three hundred forty-nine thousand, eight (h) two billion, nine hundred ten million, seven hundred six thousand, fifty (i) one hundred sixty-two billion, eighty-three million, four hundred thousand (j) eighty billion, three hundred seven million, five thousand, two hundred 3. Give the place value of each underlined digit in each whole number. (a) 42 937 050 (b) 152 856 200 (c) 894 751 (d) 23 872 000 000 (e) 6 930 850 000 NSSAL ©2013 4 Draft C. D. Pilmer 4. Write each number in expanded form. (a) 4 296 (b) 136 942 (c) 6 056 730 (d) 45 760 500 (e) 9 602 000 000 5. Order the numbers from smallest to largest. (a) 546, 93, 3, 800, 52, 9 (b) 8 700, 27, 529, 29, 8 698, 546 (c) 796, 34 000, 9 360, 790, 33 870, 9 502 (d) 56 943, 38 500, 38 099, 102 000, 56 899, 76 000 6. Matching Question You do not have to look up any of this information; you will likely be able to match most of these correctly using existing knowledge (and some common sense). (a) Average Canadian Mortgage in 2013 $500 000 (b) Province of Nova Scotia's Debt in 2012 $2200 (c) Approximate Cost of a New Family Sedan $14 000 000 000 (d) Approximate Cost of a 42 inch Flat Screen TV $40 000 (e) Overall Cost of 3 Year Phone Plan with Data Package $245 000 (f) Average Individual Income of Nova Scotian in 2010 $600 000 000 000 (g) Canada's Federal Debt in 2012 $159 000 000 (h) Cost of Purchasing a Tim Hortons' Franchise in 2012 $500 (i) Estimated Cost of New Halifax Convention Center $26 000 NSSAL ©2013 5 Draft C. D. Pilmer 7. Determine the number(s). Four examples have been provided. Number e.g. What whole number is before 23 120? 23 119 e.g. What whole number is between 1 456 and 1458? 1 457 e.g. What whole number is after 59999? 60000 e.g. What whole numbers are between 498 and 502? (a) What whole number is after 325? (b) What whole number is before 6 421? (c) What whole number is between 45 188 and 45 190? (d) What whole numbers are between 763 and 768? (e) What whole number is after 7 239? (f) What whole number is between 9 398 and 9400? (g) What whole number is before 82 600? (h) What whole number is between 62 985 and 62 987? (i) What whole numbers are between 69 997 and 70 000? (j) What whole number is before 120 000? (k) What whole number is before 7 300 000? (l) What whole numbers are between 27 029 and 27 032? 499, 500, 501 (m) What whole number is after 15 999? (n) What whole number is between 386 638 and 386 640? (o) What whole numbers are between 9 997 and 10 001? (p) What whole number is before 430 000 000? (q) What whole number is after 549 999? (r) What whole number is between 31 652 and 31 654? (s) What whole numbers are between 72 999 and 73 002? NSSAL ©2013 6 Draft C. D. Pilmer Math Facts: Addition and Multiplication Calculators, especially graphing calculators, and calculator applications for smartphones or tablets have revolutionized the mathematics one can access and learn. Teacher, instructors and professors recognize that these devices have a place in today's classrooms. However, calculators are not always to most efficient way to complete a mathematical task, and they don't replace the thinking and problem solving necessary in mathematics. In terms of efficiency, does it make sense to grab a calculator to complete simple calculations like 7 4 , 8 3 , 9 6 , and 24 3 ? If you know the math facts, then these types of questions can be completely mentally in a split second. In these cases, it takes longer to obtain the answer using a calculator. In terms of thinking and problem solving, consider the following tasks. Find the least common multiple of 6 and 8. (Answer: 24) Find the greatest common factor of 35 and 49. (Answer: 7) Complete the prime factorization of the number 90. (Answer: 90 2 3 3 5 ) Find the two numbers that multiply to give 30 and add to give 17. (Answer: 2 and 15) The calculator doesn't possess the mental flexibility (i.e. the thinking skills) necessary to complete the questions above. However, you, armed with the math facts, are more than capable of solving these types of questions. Taking the time to learn the math facts will ultimately be beneficially to your learning. If you choose not to do so, you will likely reach an impasse in this course or another. Addition Facts + 0 1 2 3 4 5 6 7 8 9 10 0 0 1 2 3 4 5 6 7 8 9 10 1 1 2 3 4 5 6 7 8 9 10 11 2 2 3 4 5 6 7 8 9 10 11 12 3 3 4 5 6 7 8 9 10 11 12 13 4 4 5 6 7 8 9 10 11 12 13 14 5 5 6 7 8 9 10 11 12 13 14 15 6 6 7 8 9 10 11 12 13 14 15 16 7 7 8 9 10 11 12 13 14 15 16 17 8 8 9 10 11 12 13 14 15 16 17 18 9 9 10 11 12 13 14 15 16 17 18 19 10 10 11 12 13 14 15 16 17 18 19 20 NSSAL ©2013 7 Draft C. D. Pilmer On the previous page, you were given the addition facts table, which you are expected to know for this course. Is it really necessary to memorize all 121 entries in this table? No; there are ways to reduce the need for memorization. That is, there are strategies that can be used to help us recall these facts. You do not need to know these strategies; we are only providing them for learners who have had repeated difficulties recalling the addition facts. Addition Fact Strategies (Optional) 1. Flip Flop Notice that 6 8 14 and 8 6 14 . Similarly 3 9 12 and 9 3 12 . What we see is that changing the order in which two numbers are added has no effect on the sum. Another way of expressing this is a b b a . So when we "flip flop" the numbers, the answer remains the same. (This is referred to as the commutative property.) So why is this important? It means that almost half of the 121 entries in our addition facts table can be viewed as a duplication of another fact. If you know that 6 4 10 , then you can conclude that 4 6 10 . If you know that 9 7 16 , then you can conclude that 7 9 16 . 2. Doubles When we add same numbers together, it is the same as doubling that number. For example, 3 3 is the same as doubling 3. Many people are familiar with the concept of doubling, so it becomes an easy way to remember what you get when you add the same numbers together. 0 0 0 (double 0) 1 1 2 (double 1) 2 2 4 (double 2) 3 3 6 (double 3) 4 4 8 (double 4) 5 5 10 (double 5) 6 6 12 (double 6) 7 7 14 (double 7) 8 8 16 (double 8) 9 9 18 (double 9) 10 10 20 (double 10) 3. Nothing Changes If you have some quantity and add nothing to it, you end up with the quantity you started with (i.e. nothing changes). That is what happens when 0 is added to a number (e.g. 7 0 7 , 4 0 4 , 0 9 9 ). The "nothing changes" strategy allows one to quickly understand what happens when 0 is added to a number. 4. Next Number When you add 1 to a whole number, it means that you just find to next whole number. 1 2 3 1 3 4 1 4 5 and so on… 2 1 3 3 1 4 4 1 5 5. Next Even/Next Odd When you add 2 to a whole number you just have to find the next even or odd number depending on the number you start with. If you start with an even number and add 2, then the sum is the next even number. If you start with an odd number and add 2, then the sum is the next odd number. NSSAL ©2013 8 Draft C. D. Pilmer (Even) 24 6 42 6 (Odd) 25 7 52 7 26 8 2 8 10 62 8 8 2 10 27 9 2 9 11 729 9 2 11 and so on… and so on…. 6. Doubles Plus One This strategy combines the Double strategy (#2) and the Next Number strategy (#4). The Doubles Plus One strategy is used with questions like 2 3 , where the two numbers being added together differ by 1. For this example, the learner should mentally change 2 3 into 2 2 1. By doing so, the learner just needs to double 2 and then go to the next number. 2 3 2 2 1 4 1 5 4 5 4 4 1 8 1 9 7 8 7 7 1 14 1 15 7. Add Ten, Then Subtract One This strategy is used when adding 9 to a number (e.g. 9 6 ). This strategy relies on the fact that most people are comfortable adding 10 to a number (e.g. 10 3 13 , 7 10 17 ). So if we want to add 9 and 4 (i.e. 9 4 ), we will add 10 and 4, then compensate by subtracting 1 (i.e. 10 4 1). 9 4 10 4 1 14 1 13 9 6 10 6 1 16 1 15 9 7 10 7 1 17 1 16 8. Add Ten, Then Subtract Two This strategy is very similar to the last strategy except it is used when adding 8 to a number (e.g. 8 6 ). Again, this strategy relies on the fact that most people are comfortable adding 10 to a number (e.g. 10 3 13 , 7 10 17 ). So if we want to add 8 and 4 (i.e. 8 4 ), we will add 10 and 4, then compensate by subtracting 2 (i.e. 10 4 2 ). 8 4 10 4 2 14 2 12 8 6 10 6 2 16 2 14 8 7 10 7 2 17 2 15 If you use all of these strategies, there are only six addition facts that you are forced to memorize. 53 8 63 9 6 4 10 7 3 10 7 4 11 7 5 12 NSSAL ©2013 9 Draft C. D. Pilmer Overview of the Addition Fact Strategies: 1. Flip Flop: The order when doing addition makes no difference 3 5 5 3 8 2. Doubles: Adding the same two numbers together is the same as doubling the number. 3. Nothing Changes: Nothing changes when you add 0. 4. Next Number: When adding 1, just count up to the next number. 5. Next Even/Next Odd: Used when adding 2. 6. Doubles Plus One: Used when adding 3. 7. Add Ten, Then Subtract One: Used when adding 9. 8. Add Ten, Then Subtract Two: Used when adding 8. Multiplication Facts 0 1 2 3 4 5 6 7 8 9 10 0 0 0 0 0 0 0 0 0 0 0 0 1 0 1 2 3 4 5 6 7 8 9 10 2 0 2 4 6 8 10 12 14 16 18 20 3 0 3 6 9 12 15 18 21 24 27 30 4 0 4 8 12 16 20 24 28 32 36 40 5 0 5 10 15 20 25 30 35 40 45 50 6 0 6 12 18 24 30 36 42 48 54 60 7 0 7 14 21 28 35 42 49 56 63 70 8 0 8 16 24 32 40 48 56 64 72 80 9 0 9 18 27 36 45 54 63 72 81 90 10 0 10 20 30 40 50 60 70 80 90 100 Again, is it really necessary to memorize all 121 entries in this table? No; there are ways to reduce the need for memorization. That is, there are strategies that can be used to help us recall these facts. You do not need to know these strategies; we are only providing them for learners who have had repeated difficulties recalling the multiplication facts. NSSAL ©2013 10 Draft C. D. Pilmer Multiplication Fact Strategies (Optional) 1. Flip Flop Notice that 5 8 40 and 8 5 40 . Similarly 6 9 54 and 9 6 54 . What we see is that changing the order in which two numbers are multiplied has no effect on the product. Another way of expressing this is a b b a . So when we "flip flop" the numbers, the answer remains the same. (This is referred to as the commutative property.) So why is this important? It means that almost half of the 121 entries in our multiplication facts table can be viewed as a duplication of another fact. If you know that 6 4 24 , then you can conclude that 4 6 24 . If you know that 7 9 63 , then you can conclude that 9 7 63 . 2. Doubles Multiplying a number by 2 is the same as doubling the number. 2 4 8 (double 4) 2 6 12 (double 6) 2 9 18 (double 9) 3. The Nine Pattern Look at the multiplication facts for nine listed below. There are two patterns here we can exploit. 9 9 81 8 9 72 7 9 63 6 9 54 5 9 45 4 9 36 Notice that the product’s tens digit is one less than the first factor. e.g. 4 9 36 e.g. 7 9 63 e.g. 8 9 72 Also notice that the sum of the digits for any of these products is 9. e.g. 4 9 36 3 6 9 3 9 27 2 9 18 e.g. 8 9 72 729 e.g. 9 9 81 8 1 9 4. The Five Chant Most people remember that when multiplying a whole number by 5, the last digit in the resulting product ends in 5 or 0 (e.g. 7 5 35 , e.g. 8 5 40 ). However, it's the five chant that most people use to recall the multiplication facts for 5. "five, ten, fifteen, twenty, twenty-five, thirty, thirty-five, forty, forty-five, fifty" 5. Snake Legs People often confuse the rule for multiplying by 0 with the rule for adding 0. For the question 5 0 or 0 5 , learners need to remember that these mean 5 sets of 0, or 0 sets of 5. In either case, the answer is 0. The easiest way to remember this is to use the snake leg strategy. How many legs does one snake have? (Answer: 0) How many legs do five snakes? (Again the answer is 0). Therefore, we can conclude that 5 0 0 . 3 0 0 6 0 0 8 0 0 (3 snakes have 0 legs) (6 snakes have 0 legs) (8 snakes have 0 legs) NSSAL ©2013 11 Draft C. D. Pilmer 6. No Change The product of 1 and another number will be the other number. There is no change. For the question 4 1 or 1 4 , learners should think of it as 4 sets of 1, or 1 set of 4. In either case, the answer is 4. We started with 4 and ended with 4; there was no change. 1 7 7 1 4 4 1 9 9 7. Tic Tac Toe Threes This technique allows one to quickly generate a 3 by 3 grid of the multiplication facts for 3. Step 1: Draw a tic tac toe grid Step 2: Starting in the lower left hand corner, moving up and then over to the next column, fill in the numbers 1 to 9. 3 6 9 2 5 8 1 4 7 Step 3: Take all the numbers in the middle row and give them a tens digit of 1. Take all the numbers in the bottom row and give them a tens digit of 2 3 6 9 12 15 18 21 24 27 If you look at the grid, you will notice that you have all the multiplication facts for 3. 31 = 3 3 2 =6 33 = 9 3 4 = 12 etc. 8. Double Double Multiplying a number by 4 is the same as doubling the number and then doubling that new answer. If you have 4 6 , then you double 6 and then double that answer. 4 6 22 6 212 24 NSSAL ©2013 Double 6 Double 12 12 Draft C. D. Pilmer 4 3 2 2 3 4 4 2 2 4 4 7 2 2 7 2 6 2 8 2 14 12 16 28 This strategy works nicely for questions like 4 4 , 4 6 , and 4 7 . It is, however, more challenging for 4 8 because many people find it difficult to mentally double 16. If you use all of these strategies, there are only six multiplication facts that you are forced to memorize. 6 6 36 6 7 42 6 8 48 7 7 49 7 8 56 8 8 64 Overview of the Addition Fact Strategies: 1. Flip Flop: The order when doing multiplication makes no difference 3 5 5 3 15 . 2. Doubling: Multiplying a number by 2 is the same as double the number. 3. The Nine Patterns: Two patterns can be exploited to remember the multiplication facts for 9. 4. The Five Chant: "five, ten, fifteen, twenty, twenty-five,…" 5. Snake Legs: Used when multiplying by 0. 6. No Change: Used when multiplying by 1. 7. Tic Tac Toe Threes: Used when multiplying by 3 8. Double Double: Used when multiplying by 4. Questions You are not permitted to use a calculator, addition tables or multiplication tables to complete these questions. 1. Fill in the blanks. (a) 7 3 _____ (b) 5 1 _____ (c) 6 6 _____ (d) 0 8 _____ (e) 4 3 _____ (f) 1 8 _____ (g) 6 2 _____ (h) 8 8 _____ (i) 3 6 _____ (j) 5 9 _____ (k) 7 2 _____ (l) 5 6 _____ NSSAL ©2013 13 Draft C. D. Pilmer (m) 9 1 _____ (n) 4 8 _____ (o) 2 0 _____ (p) 7 5 _____ (q) 9 4 _____ (r) 7 4 _____ (s) 2 9 _____ (t) 3 2 _____ (u) 6 7 _____ (v) 8 5 _____ (w) 5 4 _____ (x) 3 1 _____ (y) 4 4 _____ (z) 3 5 _____ 2. Fill in the blanks. (a) 4 2 _____ (b) 5 7 _____ (c) 1 8 _____ (d) 6 0 _____ (e) 3 9 _____ (f) 7 4 _____ (g) 4 3 _____ (h) 7 7 _____ (i) 0 9 _____ (j) 2 6 _____ (k) 5 1 _____ (l) 9 8 _____ (m) 6 8 _____ (n) 3 8 _____ (o) 6 9 _____ (p) 4 5 _____ (q) 3 7 _____ (r) 8 8 _____ (s) 8 2 _____ (t) 6 3 _____ (u) 5 6 _____ (v) 4 9 _____ (w) 9 7 _____ (x) 3 6 _____ (y) 9 5 _____ (z) 8 7 _____ 3. Indicate whether the following phrase implies the operation of addition or multiplication. (a) "5 is increased by 7" operation: _______________________ (b) "8 plus 9" operation: _______________________ (c) "4 times 5" operation: _______________________ (d) "the sum of 3 and 5" operation: _______________________ (e) "7 is increased by a factor of 3" operation: _______________________ (f) "the product of 4 and 9" operation: _______________________ (g) "combine 3 and 9" operation: _______________________ (h) "triple the number 8" operation: _______________________ NSSAL ©2013 14 Draft C. D. Pilmer 4. Find two numbers that: (a) multiply to give 6, and add to give 5. (b) Answer: ____ & ____ (d) multiply to give 16, and add to give 10. Answer: ____ & ____ multiply to give 35, and add to give 12. (c) Answer: ____ & ____ (e) multiply to give 30, and add to give 13. multiply to give 3, and add to give 4. Answer: ____ & ____ (f) Answer: ____ & ____ multiply to give 24, and add to give 11. Answer: ____ & ____ 5. KenKen puzzles were invented in 2004 by Japanese math teacher Tetsuya Miyamoto. The goal is to fill a grid with the indicated numbers such that: no number is repeated in the same row or column, and the numbers in the cages produce the target number using the indicated operation (e.g. 6 : find the numbers that multiplied give you 6) (e.g. 5+: find the numbers that added give you 5) Complete the following KenKen Puzzles using the indicated numbers. The first four puzzles are 3 by 3 puzzles because they are comprised of three rows and three columns. The last two are 4 by 4 puzzles. (a) 2, 3, 4 Puzzle 6 6+ 5+ (b) 4, 5, 6 Puzzle 24 16+ 11+ 10+ 20 (c) 5, 6, 7 Puzzle (d) 7, 8, 9 Puzzle 30 18+ 56 42 63 35 NSSAL ©2013 24+ 72 15 Draft C. D. Pilmer (e) 2, 3, 4, 5 Puzzle (f) 6, 7, 8, 9 Puzzle 12 8+ 8 48 10 6+ 16+ 9+ 15 6 63 42 8 25+ 13+ 54 6. In the appendix of this resource, you will find Addition and Multiplication Connect Four Games. Play two rounds of an Addition Game and two rounds of a Multiplication Game with a classmate, instructor and/or family member. Record in the chart below whom you played and who won. Opponent Winner Addition Game #1 Addition Game #2 Multiplication Game #1 Multiplication Game #2 NSSAL ©2013 16 Draft C. D. Pilmer Fact Families In the last section we looked at the addition facts and multiplication facts. That leaves us with the subtraction and division facts. Are these another two sets of facts that we have to memorize? No; fact families allow us to connect our addition facts to the subtraction facts, and similarly, the multiplication facts to the division facts. For example, if you know 7 3 10 , then you also know that: 3 7 10 10 7 3 10 3 7 These four facts, two addition and two subtraction facts, are referred to as a fact family. For example, if you know 6 5 30 , then you also know that: 5 6 30 30 5 6 30 6 5 These four facts, two multiplication and two division facts, are referred to as a fact family. Questions You are not permitted to use a calculator, addition tables or multiplication tables to complete these questions. 1. Write the three other members of the corresponding fact family for each. (a) 9 5 14 (b) 4 7 28 2. Complete each of the following operations (i.e. fill in the blank) and then write the three other members of corresponding fact family. (a) 4 8 _____ (b) 7 9 _____ (c) 6 7 _____ (d) 8 3 _____ (e) 15 6 _____ (f) 10 2 _____ NSSAL ©2013 17 Draft C. D. Pilmer 3. Fill in the blanks. (a) 9 1 _____ (b) 7 2 _____ (c) 6 0 _____ (d) 5 4 _____ (e) 8 3 _____ (f) 11 4 _____ (g) 7 7 _____ (h) 14 7 _____ (i) 15 5 _____ (j) 11 6 _____ (k) 10 3 _____ (l) 8 4 _____ (m) 12 4 _____ (n) 12 9 _____ (o) 13 6 _____ (p) 9 9 _____ (q) 8 0 _____ (r) 18 9 _____ (s) 6 1 _____ (t) 11 3 _____ (u) 7 4 _____ (v) 7 5 _____ (w) 14 6 _____ (x) 12 5 _____ (y) 10 7 _____ (z) 11 9 _____ 4. Fill in the blanks. (a) 14 2 _____ (b) 18 6 _____ (c) 30 5 _____ (d) 8 1 _____ (e) 7 7 _____ (f) 10 2 _____ (g) 16 8 _____ (h) 30 6 _____ (i) 27 9 _____ (j) 12 3 _____ (k) 28 4 _____ (l) 32 8 _____ (m) 45 9 _____ (n) 81 9 _____ (o) 6 3 _____ (p) 40 5 _____ (q) 42 7 _____ (r) 48 6 _____ (s) 20 4 _____ (t) 36 6 _____ (u) 63 9 _____ (v) 54 6 _____ (w) 21 7 _____ (x) 9 9 _____ (y) 72 9 _____ (z) 24 4 _____ 5. Fill in the blanks. (a) 9 4 _____ (b) 63 7 _____ (c) 3 5 _____ (d) 7 7 _____ (e) 8 3 _____ (f) 12 5 _____ NSSAL ©2013 18 Draft C. D. Pilmer (g) 2 7 _____ (h) 36 4 _____ (i) 2 8 _____ (j) 35 5 _____ (k) 8 5 _____ (l) 15 6 _____ (m) 3 3 _____ (n) 54 9 _____ (o) 14 8 _____ (p) 4 6 _____ (q) 4 8 _____ (r) 3 4 _____ (s) 6 5 _____ (t) 9 5 _____ (u) 6 1 _____ (v) 3 0 _____ (w) 6 6 _____ (x) 5 5 _____ 6. Find two numbers that: (a) multiply to give 15, and add to give 8. (b) Answer: ____ & ____ (d) multiply to give 12, and add to give 13. multiply to give 16, and add to give 8. (e) multiply to give 12, and add to give 8. (h) (k) multiply to give 9, and differ by 8. (b) multiply to give 24, and differ by 5. Answer: ____ & ____ NSSAL ©2013 (i) multiply to give 10, and add to give 11. multiply to give 10, and differ by 3. (e) multiply to give 16, and differ by 0. (l) multiply to give 0, and differ by 2. Answer: ____ & ____ 19 multiply to give 25, and add to give 10. Answer: ____ & ____ (c) multiply to give 12, and differ by 1. Answer: ____ & ____ (f) Answer: ____ & ____ (h) multiply to give 36, and add to give 13. Answer: ____ & ____ Answer: ____ & ____ Answer: ____ & ____ (g) multiply to give 24, and add to give 10. multiply to give 40, and add to give 13. Answer: ____ & ____ Answer: ____ & ____ Answer: ____ & ____ (d) (f) Answer: ____ & ____ Answer: ____ & ____ 7. Find two numbers that: (a) multiply to give 35, and differ by 2. multiply to give 18, and add to give 9. multiply to give 28, and add to give 11. Answer: ____ & ____ Answer: ____ & ____ Answer: ____ & ____ (j) (c) Answer: ____ & ____ Answer: ____ & ____ (g) multiply to give 20, and add to give 12. multiply to give 18, and differ by 7. Answer: ____ & ____ (i) multiply to give 20, and differ by 8. Answer: ____ & ____ Draft C. D. Pilmer 8. For each number, express it as: At least two number sentences involving addition, At least two number sentences involving subtraction, At least two number sentences involving multiplication, and At least two number sentences involving division. (Please note that answers will vary from learner to learner.) Example: Number 10 Two number sentences involving addition: 6 4 10 , 5 5 10 Two number sentences involving subtraction: 12 2 10 , 29 19 10 Two number sentences involving multiplication: 1 10 10 , 2 5 10 Two number sentences involving division: 30 3 10 , 80 8 10 (a) Number 6 (b) Number 8 9. Use the numbers in the charts below to complete the following RAD puzzles. (a) (b) 6 = = - 13 - + = 2 - = 3 = 30 = = = = = 10 = = = 24 + 1 6 NSSAL ©2013 1 7 5 32 = = 2 8 = 3 9 = = = = 4 = = = + 3 3 3 5 10 14 15 31 0 6 20 3 = 3 - = = 40 + = 1 8 = 6 - = = 1 8 = 1 8 + 1 8 2 9 = - 2 9 3 3 4 12 14 18 Draft C. D. Pilmer 10. Indicate whether the following phrase implies the operation of addition, subtraction, multiplication, or division. (a) "how many times does 6 go into 18?" operation: _______________________ (b) "take 9 and make it 5 times larger" operation: _______________________ (c) "12 is decreased by 7" operation: _______________________ (d) "the total of 6 and 12" operation: _______________________ (e) "5 is removed from 9" operation: _______________________ (f) "break 12 into 4 equal parts" operation: _______________________ 11. In the appendix of this resource, you will find Subtraction and Division Connect Four Games. Play two rounds of a Subtraction Game and two rounds of the Division Game with a classmate, instructor and/or family member. Record in the chart below whom you played and who won. Opponent Winner Subtraction Game #1 Subtraction Game #2 Division Game #1 Division Game #2 NSSAL ©2013 21 Draft C. D. Pilmer Order of Operations Exponents Before we talk about order of operations, we need to talk about exponents, specifically the exponents of 2 and 3. When a number is raised to an exponent of 2 (i.e. the number is being squared), you are multiplying the number by itself. e.g. 32 3 3 9 e.g. 62 6 6 36 e.g. 72 7 7 49 When a number is raised to an exponent of 3 (i.e. the number is being cubed), you are multiplying the number by itself three times. e.g. 23 2 2 2 8 e.g. 33 3 3 3 27 e.g. 53 5 5 5 125 Order of Operations Below, the same question was done by four different learners. The problem was that everyone ended up with different answers. Kimi's Answer: Ryan's Answer Paulette's Answer Ajay's Answer 4 5 2 4 5 2 4 5 2 4 5 2 2 2 2 2 20 22 20 4 16 4 32 49 36 45 4 4 1 4 122 144 Kimi started with the multiplication, followed by the squaring, and then did the subtraction. Ryan started with the operation in the brackets, followed by the squaring, and then did the multiplication. Paulette started with the squaring, followed by the subtraction, and then did the multiplication. Ajay started with the operation in the brackets, followed by the multiplication, and then did the squaring. 4 32 All of these learners started with the same question, but ended up with very different answers based on the order they chose to do the operations. Only one of the learners is correct. Do you know which one? The correct answer is 36. Ryan did the question correctly because he knew the order of operations, the rules used to clarify which mathematical operations are done first in a mathematical expression. The proper order can be remembered using the acronym BEDMAS. B E DM AS NSSAL ©2013 - brackets first - then exponents (e.g. squaring, cubing) - followed by division and multiplication in the order they appear (i.e. from left to right) - followed by addition and subtraction in the order they appear (i.e. from left to right) 22 Draft C. D. Pilmer Example 1 Evaluate each of the following. (a) 5 7 3 (b) 10 3 8 4 3 3 (d) 29 3 24 6 (e) 7 5 3 7 Answers: (a) 5 7 3 5 21 26 (c) 5 32 2 2 (f) 2 7 1 1 33 The mathematical expression 5 7 3 only involves the operations of addition and multiplication. According to BEDMAS, we do multiplication before addition. (b) 10 3 8 4 10 3 2 72 9 The mathematical expression 10 3 8 4 involves the operations of subtraction, addition and multiplication. According to BEDMAS, multiplication is done before subtraction or addition. Once this is done we have to decide between the subtraction and addition. When these operations occur in the same question, we always work from left to right. That means we will do the subtraction before the addition. (c) 5 32 2 5 9 2 5 18 23 The mathematical expression 5 32 2 involves the operations of addition, squaring, and multiplication. According to BEDMAS, we would do the squaring (i.e. exponents) first, followed by multiplication, and finally the addition. (d) 29 33 24 6 29 27 24 6 29 27 4 24 6 The mathematical expression 29 33 24 6 involves the operations of subtraction, cubing, addition, and division. According to BEDMAS, we would do the cubing (i.e. exponents) first. Next we would do the division. Once this is done we have to decide between the subtraction and addition. When these operations occur in the same question, we always work from left to right. That means we will do the subtraction before the addition. (e) 7 5 With the mathematical expression 7 5 3 7 we have subtraction embedded within a set of brackets, cubing, addition, and multiplication. According to BEDMAS, we start with the operations in the brackets. This will be followed by the cubing (i.e. exponents). We will then do the multiplication, and then finish up with the addition. 3 3 7 23 3 7 8 3 7 8 21 29 NSSAL ©2013 3 23 Draft C. D. Pilmer (f) 2 7 1 1 33 2 2 7 22 33 2 7 4 27 2 28 27 30 27 3 With the mathematical expression 2 7 1 1 33 we will start with the addition that is embedded within a set of brackets. Next we will work with the exponents (i.e. the squaring and the cubing). Following this we do the multiplication. That leaves us with the addition and multiplication. When these operations occur in the same question, we always work from left to right. That means we will do the addition before the subtraction. 2 Questions 1. Evaluate each of the following. Show your work and do not use a calculator or math fact tables. (a) 10 3 2 (b) 18 10 2 (c) 9 2 3 (d) 12 6 5 (e) 3 2 6 1 (f) 8 12 4 3 (g) 12 4 3 9 (h) 7 3 16 2 (i) 5 4 2 7 2 (j) 24 42 8 (k) 25 23 3 (l) 4 2 32 NSSAL ©2013 24 Draft C. D. Pilmer (m) 2 32 5 2 (n) 10 4 32 2 (o) 5 23 10 22 (p) 62 4 2 52 (q) 10 5 1 (r) (s) 10 25 7 2 (t) (v) 3 7 5 5 (w) 7 3 3 9 2 2 7 20 33 2 3 6 23 (u) 32 5 3 3 (x) 5 7 4 1 1 3 2. Create your own expression that when correctly evaluated produces an answer of 5. Your expression must include brackets, exponents, and at least two different operations (i.e. addition, subtraction, multiplication, division). NSSAL ©2013 25 Draft C. D. Pilmer Multiples of Ten, One Hundred, and One Thousand Numbers that are multiples of ten are divisible by 10 (i.e. ten divides evenly into them). The numbers are easy to recognize because they end with a zero. Multiples of 10: 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120, 130,… Numbers that are multiples of one hundred are divisible by 100 (i.e. one hundred divides evenly into them). The numbers are easy to recognize because they end with two zeros. Multiples of 100: 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200,… Numbers that are multiples of one thousand are divisible by 1000 (i.e. one thousand divides evenly into them). The numbers are easy to recognize because they end with three zeros. Multiples of 1000: 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10000, 11000,… So obviously, a multiple of 1000, like 7000, is also a multiple of 100 and 10. Similarly, a multiple of 100, like 500, is also a multiple of 10. In this section, we will mentally add, subtract, multiply and divide whole numbers that are multiples of ten, one hundred, and one thousand. e.g. 40 50 90 e.g. 600 200 400 e.g. 40 600 12 000 e.g. 150 50 3 Addition We will only be adding "like multiples" in this section. That is, we will be adding multiples of ten with multiples of ten, adding multiples of one hundred with multiples of one hundred, and so on. e.g. 40 30 If 4 3 7 , then 40 30 must be equal to 70. e.g. 80 50 If 8 5 13 , then 80 50 must be equal to 130. e.g. 600 200 If 6 2 8 , then 600 200 must be equal to 800. e.g. 400 700 If 4 7 11 , then 400 700 must be equal to 1 100. e.g. 1 000 8 000 If 1 8 9 , then 1 000 8 000 must be equal to 9 000. e.g. 9 000 5 000 If 9 5 14 , then 9 000 5 000 must be equal to 14 000. Subtraction We will only be subtracting "like multiples" in this section. That is, we will be subtracting multiples of ten from multiples of ten, subtracting multiples of one hundred from multiples of one hundred, and so on. e.g. 90 70 If 9 7 2 , then 90 70 must be equal to 20. e.g. 140 80 If 14 8 6 , then 140 80 must be equal to 60. e.g. 600 200 If 6 2 4 , then 600 200 must be equal to 400. e.g. 1 500 700 If 15 7 8 , then 1 500 700 must be equal to 800. e.g. 8 000 5 000 If 8 5 3 , then 8 000 5 000 must be equal to 3 000. e.g. 14 000 5 000 If 14 5 9 , then 14 000 5 000 must be equal to 9 000. NSSAL ©2013 26 Draft C. D. Pilmer Multiplication Many of you are likely familiar with the three step process for completing the type of multiplication shown below. You are not expected to show this process; rather complete the work in your head. e.g. Evaluate 80 6 . Answer: To work out 80 6 , it is a three step process. (i) Omitting the zeros, multiply the two numbers ( 8 6 48 ) (ii) Next count the number of zeros in the original question (There is 1; one from the number 80 and none from the 6) (iii)Take the product from step (a) and tack on the number of zeros from step (b). Therefore: 80 6 = 480 e.g. Evaluate 90 50 . Answer: To work out 90 50 , it is a three step process (i) Omitting the zeros, multiply the two numbers ( 9 5 45 ) (ii) Next count the number of zeros in the original question (There are 2; one from the number 90 and one from the 50) (iii)Take the product from step (a) and tack on the number of zeros from step (b). Therefore: 90 50 = 4 500 e.g. Evaluate 400 70 . Answer: To work out 400 70 , it is a three step process (i) Omitting the zeros, multiply the two numbers ( 4 7 28 ) (ii) Next count the number of zeros in the original question (There are 3; two from the number 400 and one from the 70) (iii)Take the product from step (a) and tack on the number of zeros from step (b). Therefore: 400 70 = 28 000 Division With these questions, we are going to show you two approaches; you choose the approach that you prefer. Like multiplication, we expect that all this work will be done mentally, as opposed to writing everything out using pencil and paper. e.g. 160 4 Answer: Method 1: Use Related Multiplication Fact Based on our work with fact families in the previous section, we know that operations of multiplication and division are connected to each other. So when we are asked, "What is 160 divided by 4?" (i.e. 160 4 ), we know that this can be restated as, "What multiplied by 4, gives us 160?" (i.e. ? 4 160 ). Many realize that 40 multiplied by 4 gives 160. Therefore 160 4 40 NSSAL ©2013 27 Draft C. D. Pilmer Method 2: Number of Sets Knowing that 16 4 4 can help one answer 160 4 . The question that remains is whether 160 4 is equal to 4, 40, or 400? The way to decide is to determine how many sets of 4 are in 160. Logically, there are 40 sets of 4 in 160. Therefore 160 4 40 . e.g. 560 70 Answer: Method 1: Use Related Multiplication Fact "What is 560 divided by 70?" (i.e. 560 70 ), can be restated as, "What multiplied by 70, gives us 560?" (i.e. ? 70 560 ). Many realize that 8 multiplied by 70 gives 560. Therefore 560 70 8 Method 2: Number of Sets Knowing that 56 7 8 can help one answer 560 70 . The question that remains is whether 560 70 is equal to 8, 80, or 800? The way to decide is to determine how many sets of 70 are in 560. Logically, there are 8 sets of 70 in 560. Therefore 560 70 8 . e.g. 4 500 5 Answer: Method 1: Use Related Multiplication Fact "What is 4500 divided by 5?" (i.e. 4 500 5 ), can be restated as, "What multiplied by 5, gives us 4500?" (i.e. ? 5 4 500 ). Many realize that 900 multiplied by 5 gives 4 500. Therefore 4 500 5 900 Method 2: Number of Sets Knowing that 45 5 9 can help one answer 4 500 5 . The question that remains is whether 4 500 5 is equal to 9, 90, or 900? The way to decide is to determine how many sets of 5 are in 4 500. Logically, there are 900 sets of 5 in 4 500. Therefore 4 500 5 900 . e.g. 2 800 40 Answer: Method 1: Use Related Multiplication Fact The question can restated as, "What multiplied by 40, gives us 2 800?" (i.e. ? 40 2 800 ). Many realize that 70 multiplied by 40 gives 2 800. Therefore 2 800 40 70 Method 2: Number of Sets Knowing that 28 4 7 can help one answer 2 800 40 . The question that remains is whether 2 800 40 is equal to 7, 70, or 700? The way to decide is to determine how many sets of 400 are in 2 800. Logically, there are 60 sets of 40 in 2 800. Therefore 2 800 40 70 . NSSAL ©2013 28 Draft C. D. Pilmer e.g. 2 700 900 Answer: Method 1: Use Related Multiplication Fact The question can be restated as, "What multiplied by 900, gives us 2 700?" (i.e. ? 900 2 700 ). Many realize that 3 multiplied by 900 gives 2 700. Therefore 2 700 900 3 Method 2: Number of Sets Knowing that 27 9 3 can help one answer 2 700 900 . The question that remains is whether 2 700 900 is equal to 3, 30, or 300? The way to decide is to determine how many sets of 900 are in 2 700. Logically, there are 3 sets of 900 in 2 700. Therefore 2700 900 3 . Questions You are not permitted to use a calculator, addition tables or multiplication tables to complete these questions. 1. (a) 20 60 _______ (b) 500 400 _______ (c) 60 60 _______ (d) 5000 3000 _______ (e) 600 300 _______ (f) 1000 8000 _______ (g) 90 60 _______ (h) 700 400 _______ (i) 40 40 _______ (j) 800 600 _______ (k) 5000 6000 _______ (l) 900 700 _______ 2. (a) 70 40 _______ (b) 500 100 _______ (c) 6 000 6 000 _______ (d) 800 200 _______ (e) 7 000 3 000 _______ (f) 90 70 _______ (g) 1 200 500 _______ (h) 170 90 _______ (i) 13 000 4 000 _______ (j) 150 80 _______ (k) 1 100 300 _______ (l) 14 000 7 000 _______ (b) 30 50 _______ (c) 2000 8 _______ (d) 90 400 _______ (e) 60 80 _______ (f) 50 5 _______ (g) 600 40 _______ (h) 90 90 _______ (i) 8 300 _______ (j) 5 70 _______ (k) 6 7000 _______ (l) 80 100 _______ 3. (a) 7 30 _______ NSSAL ©2013 29 Draft C. D. Pilmer 4. (a) 320 8 _______ (b) 280 70 _______ (c) 420 60 _______ (d) 4 500 50 _______ (e) 5 400 600 _______ (f) 140 2 _______ (g) 1 500 5 _______ (h) 480 60 _______ (i) 1 800 900 _______ (j) 6400 80 _______ (k) 490 7 _______ (l) 3500 7 _______ (m) 7 200 9 _______ (n) 160 80 _______ (o) 1 200 20 _______ (p) 210 3 _______ (q) 2 500 500 _______ (r) 3600 6 _______ 5. (a) 70 20 _______ (b) 400 8 _______ (c) 1 400 900 _______ (d) 80 30 _______ (e) 90 80 _______ (f) 3 90 _______ (g) 4200 7 _______ (h) 800 500 _______ (i) 12 000 7 000 _______ (j) 40 40 _______ (k) 2400 800 _______ (l) 8 000 6 000 _______ (m) 700 600 _______ (n) 800 400 _______ (o) 2800 40 _______ (p) 70 10 _______ (q) 700 80 _______ (r) 130 90 _______ (s) 4 200 60 _______ (t) 40 80 _______ (u) 270 30 _______ 6. Find two digit numbers, which are also multiples of ten, that: (a) multiply to give 800, (b) multiply to give 1200, (c) and add to give 60. and add to give 70. Answer: _______ & _______ (d) multiply to give 8100, and add to give 180. Answer: _______ & _______ (e) Answer: _______ & _______ (g) multiply to give 1800, and differ by 30. Answer: _______ & _______ NSSAL ©2013 multiply to give 5400, and add to give 150. Answer: _______ & _______ (f) Answer: _______ & _______ (h) multiply to give 4200, and differ by 10. Answer: _______ & _______ 30 multiply to give 3500, and add to give 120. multiply to give 1600, and differ by 60. Answer: _______ & _______ (i) multiply to give 3600, and differ by 50. Answer: _______ & _______ Draft C. D. Pilmer 7. With KenKen puzzles, the goal is to fill a grid with the indicated numbers such that: no number is repeated in the same row or column, and the numbers in the cages produce the target number using the indicated operation (e.g. 600 : find the numbers that multiplied give you 600) (e.g. 50+: find the numbers that added give you 50) Complete the following KenKen Puzzles using the indicated numbers. (a) 10, 20, 30 Puzzle 600 (b) 20, 30, 40 Puzzle 300 50+ 50+ 70+ 1200 800 40+ 20 (c) 30, 40, 50 Puzzle 1500 (d) 40, 50, 60 Puzzle 120+ 90+ 150+ 1200 3000 (e) 50, 60, 70 Puzzle 4200 110+ 2400 90+ (f) 70, 80, 90 Puzzle 3000 170+ 6300 190+ 70 5600 7200 NSSAL ©2013 31 Draft C. D. Pilmer 8. Use the numbers in the charts below to complete the following RAD puzzles. (a) 3 = - = 40 + - + - = = = 27 = = = 3 = = 60 = + = = 20 = 240 + 0 30 - 2 30 = 4 30 5 30 = 6 40 9 50 20 60 21 90 = 200 + 24 180 (b) - = + - = = = 20 = 30 = = 1200 = 2 = = = = = + + - 30 0 40 2 60 4 70 = 300 = 5 100 7 200 10 600 10 900 20 1200 40 1400 9. There are flashcards in the appendix of this resource. Over the next few days, regularly use these cards and see how fast you can answer 40 randomly selected cards. Record your best three times. _________ _________ _________ NSSAL ©2013 32 Draft C. D. Pilmer Divisibility and Prime Divisibility: When one number can be divided by another and the result is an exact whole number (i.e. no remainder). For example, 18 is divisible by 3, because 18 3 6 exactly. However, 11 is not divisible by 5 because 11 5 2 with a remainder of 1. Divisibility Rules: Numbers that are divisible by 2 are even numbers. e.g. 6, 34, 798, 2050, and 3942 are all divisible by 2 If the sum of the digits of a multi-digit number produces a number that is divisible by three, then the original multi-digit number is divisible by 3. e.g. 72 is divisible by 3 because 7 + 2 = 9 and 9 is divisible by 3. e.g. 561 is divisible by 3 because 5 + 6 + 1 = 12 and 12 is divisible by 3. If the ones digit is a 0 or a 5, then the number is divisible by 5. e.g. 75, 120, 375, and 2960 are all divisible by 5. If a number is divisible by 2 (i.e. an even number) and divisible by 3 (i.e. sum of the digits is a number divisible by 3), then the number is divisible by 6. e.g. 48 is divisible by both 2 and 3, and therefore divisible by 6. e.g. 132 is divisible by both 2 and 3, and therefore divisible by 6. If a number is only divisible by itself and 1, then the number is prime. e.g. 2, 3, 17, 41, and 89 are all prime numbers Questions 1. Beside each number you will find a box corresponding to a number that might divide evenly into the original number. Check off the appropriate boxes to identify whether the original number is divisible by 2, 3, 5 and/or 6, or a prime number (P). Do not use a calculator. e.g. 78 (a) 2 3 5 6 P 2 e.g. 345 22 (b) 55 (c) 13 (d) 72 (e) 75 (f) 29 (g) 90 (h) 63 (i) 61 (j) 86 (k) 261 (l) 440 (m) 428 (n) 546 NSSAL ©2013 33 3 5 6 P Draft C. D. Pilmer 2 3 5 6 P 2 (o) 417 (p) 948 (q) 510 (r) 179 (s) 8001 (t) 4315 (u) 3218 (v) 5202 (w) 2870 (x) 1320 (y) 2853 (z) 7302 3 5 6 P 2. For this question, do not use any of the numbers that you encountered in question 1. (a) Create a three digit number that is divisible by 2, but not divisible by 3, 5, or 6. _______ (b) Create a three digit number that is divisible by 3, but not divisible by 2, 5, or 6. _______ (c) Create a three digit number that is divisible by 5, but not divisible by 2, 3, or 6. _______ (d) Create a three digit number that is divisible by 2 and 5, but not divisible by 3. _______ (e) Create a three digit number that is divisible by 3 and 5, but not divisible by 2. _______ NSSAL ©2013 34 Draft C. D. Pilmer Estimating In the sections following this one, we will learning how to add subtract, multiply, and divide multi-digit numbers. When learners do these types, they sometimes do not take the time to judge the reasonableness of their final answer. Often they are just pleased to get through the question and do not spend additional time to know if their answer is "in-the-ballpark." In reality, it only takes a few seconds to determine whether your answer is reasonable; it all comes down to using estimation skills. Another issue is that many individuals have become so dependent on calculators that they are unaware when the device outputs an unreasonable answer, often because the user has pressed the wrong key or omitted a decimal point or digit. Using your estimation skills can prevent one from blindly accepting an unreasonable output from a calculator. Example 1 Hannah completed the question 118 42 and obtained an answer of 4956. Is her answer reasonable? Answer: Please note that this question is not asking whether Hannah's answer is correct; rather, it is asking whether it is reasonable. If you were checking the answer, you would work it out in full using paper and pencil, or check it with a calculator. However, to judge the reasonableness of Hannah's answer, we can use a variety of estimation strategies. We have shown several acceptable ways of handling this question below. Estimate 1: 120 40 4800 Estimate 2: 100 50 5000 Estimate 3: 110 40 4400 110 50 5500 Between 4400 and 5500 Change 118 to 120, and change 42 to 40. By increasing one number slightly and decreasing the other number slightly, the estimate should be fairly close to the actual answer. This technique is only useful if you can mentally multiply 12 by 4. Change 118 to 100 and change 42 up to 50. We decreased one number significantly and increased the other number significantly, but the estimate is still fairly close to the actual answer. Change 118 to 110 and 42 to 40, and then 50. In this case, they calculate two estimates; one whose product is likely under the actual answer, and one whose product is likely over. They concluded that the real answer should be between 4400 and 5500. Regardless of the estimation strategy used, all three techniques illustrate that Hannah's answer of 4956 is reasonable. NSSAL ©2013 35 Draft C. D. Pilmer Example 2 Samir completed the question 356 248 109 and obtained an answer of 893. Is his answer reasonable? Answer: Again, we have shown a variety of acceptable estimation strategies that can be used to handle this question. Estimate 1: 350 250 110 710 Estimate 2: 400 200 100 700 Estimate 3: 300 200 100 600 400 300 100 800 Between 600 and 800 Change 356 to 350, change 248 to 250, and change 109 to 110. This technique is only useful if you are comfortable mentally adding 350 and 250. This estimate should be fairly close to the actual answer. Change 356 to 400, change 248 to 200, and change 109 to 100. The first number, 356, was increased by almost 50, and the second number, 248, was decreased by almost 50. Increasing one number significantly and decreasing the second number by roughly the same amount will not greatly affect the sum. This estimate should be fairly close to the actual answer. In this case, they calculate two estimates; one whose sum is likely under the actual answer, and one whose sum is likely over. They concluded that the real answer should be between 600 and 800. Regardless of the estimation strategy used, all three techniques illustrate that Samir's answer of 893 is unreasonable. Questions Do not use a calculator to complete any of these questions. 1. In each case, indicate whether the answer is reasonable or unreasonable. Show your work in the space provided on the right (i.e. show the estimation technique that you employed). (a) 1852 1179 3031 Reasonable Unreasonable (b) 61 89 5429 Reasonable Unreasonable (c) 1260 4 315 Reasonable NSSAL ©2013 Unreasonable 36 Draft C. D. Pilmer (d) 488 307 685 Reasonable Unreasonable (e) 919 228 691 Reasonable Unreasonable (f) 395 79 50 Reasonable Unreasonable (g) 201 72 1512 Reasonable Unreasonable (h) 648 553 95 Reasonable Unreasonable 2. In each case, find in the missing digit. (a) If __845 6 is about 300, then what number should be filled in to replace the missing digit? ______ (b) If __2 81 is close to 3400, then what number should be filled in to replace the missing digit? ______ (c) If __49 - 754 is about 200, then what number should be filled in to replace the missing digit? ______ (d) If 3945 + __078 is close to 6000, then what number should be filled in to replace the missing digit? ______ (e) If __95 5 is about 80, then what number should be filled in to replace the missing digit? ______ (f) If __93 + 389 is almost 900, then what number should be filled in to replace the missing digit? ______ (g) If 71 __9 is close to 6300, then what number should be filled in to replace the missing digit? ______ NSSAL ©2013 37 Draft C. D. Pilmer Adding Multi-Digit Numbers To add multi-digit whole numbers, start by stacking the numbers vertically such that corresponding place values line up (e.g. units with units, tens with tens) and add from right to left. If the sum in any corresponding place value is 10 or greater, we regroup (i.e. carry the excess to the next larger place value). e.g. 324 + 45 Answer: Stack the numbers vertically (i.e. one on top of another) such corresponding place values line up. Add the Units Add the Tens Add the Hundreds 3 2 4 4 5 3 2 4 4 5 3 2 4 4 5 9 6 9 3 6 9 4 units plus 5 units is 9 units. 2 tens plus 4 tens is 6 tens. 3 hundreds plus 0 hundreds is 3 hundreds. Does this answer of 369 look reasonable? The easiest way to check is to round the original numbers to values that we can mentally add. We can round 324 to 320, and round 45 to 50. When 320 is added to 50, we obtain 370, which is very close to the original answer of 369. Our answer looks reasonable. e.g. 158 + 265 Answer: Add the Units Add the Hundreds 1 5 8 2 6 5 1 5 8 2 6 5 1 5 8 2 6 5 3 2 3 4 2 3 1 8 units plus 5 units is 13 units. Regroup the 13 to 1 ten and 3 units. Write the 3 in the units place and carry the 1 to the next place value (tens). NSSAL ©2013 Add the Tens 1 1 1 1 1 ten plus 5 tens plus 6 1 hundred plus 1 tens is 12 tens. Regroup hundred plus 2 hundreds the 12 to 1 hundred and is 4 hundreds 2 tens. Write the 2 in the tens place and carry the 1 to the next place value (hundreds). 38 Draft C. D. Pilmer e.g. 451 + 75 + 192 Answer: Add the Units Add the Tens 4 5 1 7 5 1 9 2 4 5 1 7 5 1 9 2 8 Add the Hundreds 2 2 4 5 1 7 5 1 9 2 1 8 7 1 8 1 unit plus 5 units plus 2 5 tens plus 7 tens plus 9 units is 8 units. tens is 21 tens. Regroup the 21 to 2 hundreds and 1 ten. Write the 1 in the tens place and carry the 2 to the next place value (hundreds). 2 hundreds plus 4 hundreds plus 0 hundreds plus 1 hundred is 7 hundreds. Does this answer of 718 look reasonable? The easiest way to check is to round the original numbers to values that we can mentally add. We can round 451 to 450, round 75 to 100, and round 192 to 200. When we add 450, 100, and 200, we obtain 750. This estimate is higher than the original answer of 718, but this is to be expected because we rounded two of the numbers up significantly. Regardless of this, the answer of 718 seems reasonable. e.g. 926 + 437 e.g. 2 943 + 4 864 Answer: Answer: 1 1 1 9 2 6 4 3 7 2 9 4 3 4 8 6 4 1 3 6 3 7 8 0 7 Note: Is the technique (i.e. algorithm), which we have been teaching, the only way to add multi-digit whole numbers? No; however, it is the most commonly taught technique. Examples of other techniques are shown below. Suppose a learner was required to add 36 and 57. They could say 30 + 50 = 80, 6 + 7 = 13, and 80 + 13 = 93. Therefore 36 + 57 = 93. These individuals did not use the algorithm we have shown but obtained the correct solution using a perfectly valid method. Suppose a learner was required to add 88 and 54. They could increase the first number by 2 and decrease the second number by 2. That changes the question from 88 + 54 to 90 + 52, a question that many can solve in their head. 88 + 54 = 90 + 52 = 142 NSSAL ©2013 39 Draft C. D. Pilmer Questions Complete the following operations. Do not use a calculator or an addition facts table. 1. 2. (a) 6 3 2 5 (b) 3 8 4 6 (c) 7 5 6 1 (d) 2 4 6 5 1 3 (e) 3 2 5 3 4 7 (f) 5 0 8 9 7 7 (g) 4 2 3 3 5 1 2 6 (h) 2 5 3 4 7 6 3 4 (i) 3 6 2 7 8 4 2 9 1 (j) 3 7 5 9 1 4 2 6 (k) 6 1 5 9 8 0 4 9 (l) 8 0 1 6 5 8 8 7 1 5 6 (a) 78 + 94 (b) 367 + 243 (c) 48 + 313 + 925 3. There are 183 women and 68 men on the sales staff? How many people are on the sales staff? NSSAL ©2013 40 Draft C. D. Pilmer Subtracting Multi-Digit Numbers To subtract multi-digit whole numbers, start by stacking the numbers vertically such that corresponding place values line up (e.g. units with units, tens with tens) and subtract from right to left. If the digit being subtracted is larger than the digit from which it is being subtracted, regroup (i.e. borrow) one from the digit in the next larger place value. e.g. 597 - 62 Answer: Stack the numbers vertically (i.e. one on top of another) such corresponding place values line up. Subtract the Units Subtract the Tens Subtract the Hundreds 5 9 7 6 2 5 9 7 6 2 5 9 7 6 2 5 3 5 5 3 5 7 units minus 2 units is 5 units. 9 tens minus 6 tens is 3 tens. 5 hundreds minus 0 hundreds is 5 hundreds. To determine if our answer is reasonable, we can round 597 to 600, round 62 to 60, and take the difference. Since 600 60 540 , it appears that our answer of 535 is reasonable. e.g. 392 - 145 Answer: Subtract the Units 3 1 8 12 8 12 9 4 2 5 9 4 2 5 4 7 7 We cannot take 5 units from 2 units. Therefore we regroup (i.e. borrow) 1 from the tens, which leaves us with 8 tens and 12 units. 12 units minus 5 units is 7 units. NSSAL ©2013 Subtract the Tens 3 1 8 tens minus 4 tens is 4 tens. 41 Subtract the Hundreds 8 12 9 4 2 5 2 4 7 3 1 3 hundreds minus 1 hundred is 2 hundreds. Draft C. D. Pilmer e.g. 647 - 391 Answer: Subtract the Units 6 4 7 3 9 1 Subtract the Tens 5 14 5 14 6 3 4 9 7 1 6 3 4 9 7 1 5 6 2 5 6 6 7 units minus 1 unit is 6 units. Subtract the Hundreds We cannot take 9 tens 3 hundreds minus 1 from 4 tens. Therefore hundred is 2 hundreds. we regroup (i.e. borrow) 1 from the hundreds, which leaves us with 5 hundreds and 14 tens. 14 tens minus 9 tens is 5 tens. e.g. 934 - 268 Answer: Subtract the Units Subtract the Tens 9 4 12 12 2 14 8 2 14 8 2 14 3 6 4 8 9 4 3 6 4 8 9 4 3 6 4 8 6 6 4 6 6 6 We cannot take 8 units from 4 units. Therefore we regroup (i.e. borrow) 1 from the tens, which leaves us with 2 tens and 14 units. 14 units minus 8 units is 6 units. NSSAL ©2013 Subtract the Hundreds We cannot take 6 tens 8 hundreds minus 4 from 2 tens. Therefore hundreds is 4 hundreds. we regroup (i.e. borrow) 1 from the hundreds, which leaves us with 8 hundreds and 12 tens. 12 tens minus 6 tens is 6 tens. 42 Draft C. D. Pilmer e.g. 803 - 288 Answer: Subtract the Units Subtract the Tens Subtract the Hundreds 9 7 10 13 7 10 8 2 0 8 3 8 8 2 0 8 5 We cannot take 8 units from 3 units. Therefore we regroup (i.e. borrow). However, we have a zero in the tens place. We need to borrow 1 hundred from the hundreds place, then borrow 10 from the tens place. That leaves us with 7 hundreds, 9 tens, and 13 units. 13 units minus 8 units is 5 units. 9 13 7 10 13 3 8 8 2 0 8 3 8 5 1 5 9 1 5 9 tens minus 8 tens is 1 ten. e.g. 6 946 - 2 439 7 hundreds minus 2 hundreds is 5 hundreds. e.g. 5 248 - 761 Answer: Answer: 3 16 6 9 2 4 4 3 6 9 4 5 0 7 11 4 1 14 5 2 7 4 6 4 4 8 7 8 1 Questions Complete the following operations without using a calculator or an addition facts chart. Notice that we have included a few addition questions. 1. (a) NSSAL ©2013 7 8 5 3 (b) 8 3 2 6 43 (c) 5 6 9 7 Draft C. D. Pilmer 2. (d) 6 4 8 5 2 1 (e) 5 6 7 1 8 7 (f) 2 5 4 6 7 (g) 4 7 1 5 8 3 (h) 9 8 4 7 5 8 (i) 4 0 5 2 7 9 (j) 4 2 9 7 3 0 5 2 (k) 6 3 7 4 2 5 1 4 (l) 5 4 6 3 1 2 9 5 (m) 6 7 0 3 3 6 9 (n) 4 2 5 4 7 1 8 3 (o) 9 0 2 8 8 2 5 7 (a) 674 - 58 (b) 1 243 - 87 (c) 5 692 - 825 3. On payday Tyrus had $1250 in his chequing account. After paying his bills, his balance in this account was $367. How much did he spend on bills? 4. A power drill costs $89 (before taxes). A circular saw costs $124 (before taxes). Find the total cost for the two tools before taxes. 5. On Tuesday, 763 people attended the fair. On Wednesday, 927 people attended the fair. How many more people attended on Wednesday compared to Tuesday? NSSAL ©2013 44 Draft C. D. Pilmer Multiplying Multi-Digit Numbers In this section, we will show three ways to multiply multi-digit whole numbers: the traditional algorithm, multiplying using the expanded form, and the lattice method. You choose the technique you are most comfortable with. Example 1 Complete the following operation. 67 49 Answer: Method 1: Traditional Algorithm 6 6 7 4 9 3 6 7 4 9 6 0 3 0 2 6 7 4 9 6 0 3 2 6 8 0 Step 1: Multiply 9 by 7. The resulting product is 63. Write 3, and carry (i.e. regroup) the 6. 6 6 7 4 9 6 0 3 Step 3: Place a 0 in the units place as in our next step we will be multiplying using the second digit (tens) Step 5: Multiply 4 by 6. The resulting product is 24. Add the 2 that you carried to the 24, and write down the resulting sum. 2 6 7 4 9 Step 2: Multiply 9 by 6. The resulting product is 54. Add the 6 that you carried to the 54, and write down the resulting sum. Step 4: Multiply 4 by 7. The resulting product is 28. Write 8, and carry the 2. 6 0 3 8 0 6 7 4 9 Step 6: Add to get the desired product. 6 0 3 2 6 8 0 3 2 8 3 Method 2: Multiplying Using the Expanded Form We first need to express the two numbers in their expanded forms (67 = 60 + 7 and 49 = 40 + 9) and then set the numbers up so that we can do the multiplication. 60 7 40 9 6 5 4 2 8 2 4 0 3 0 0 0 9 7 ; first set of multiplication 9 60 ; second set of multiplication 40 7 ; third set of multiplication 40 60 ; fourth set of multiplication 3 2 8 3 NSSAL ©2013 45 Draft C. D. Pilmer Method 3: Lattice Method In this case we are multiplying a two digit number by another two digit number, therefore we create a 2 by 2 grid with diagonals drawn in each of the resulting squares. 6 7 4 6 2 4 2 4 9 Step 1: We put the 67 along the top of the chart, and the 49 along the right side of the grid. 6 7 7 2 4 8 9 9 Step 2: Multiply the 6 by the 4, and place the two digits of the product (24) in the two spaces in the upper left hand corner of the grid. Step 3: Multiply the 7 by the 4, and place the two digits of the product (28) in the two spaces in the upper right hand corner of the grid. carry 1 6 2 4 5 4 7 6 2 8 4 9 2 4 5 7 2 8 6 4 3 4 4 3 9 2 2 carry 1 2 4 5 8 6 4 3 8 3 67 49 = 3283 Step 4: Multiply the 6 by the 9, and place the two digits of the product (54) in the two spaces in the lower left hand corner of the grid. NSSAL ©2013 Step 5: Multiply the 7 by the 9, and place the two digits of the product (63) in the two spaces in the lower right hand corner of the grid. 46 Step 6: Now ignore the 67 and 49 along the outside of our grid. Starting at the bottom, add the numbers along each diagonal placing the answer along the outer edge of the chart. If a sum exceeds 9, carry the tens digit up to the next diagonal. The numbers along the outside, starting at the upper left, represent the digits of your product. Draft C. D. Pilmer Of the three methods shown, most learners find the second method the easiest to understand and the easiest to complete successfully. The author of this resource generally recommends this technique. Although, the lattice method has a "cool factor" to it, learners don't always understand why this technique works. It is actually very similar to the expanded form technique; notice that the diagonals in the lattice match the columns in the expanded form. We have a video on YouTube that explains the lattice method. Google search "YouTube Lattice Method nsccalpmath." Example 2 Complete the following operation. 497 53 Answer: Method 1: Traditional Algorithm 2 4 9 7 5 3 1 2 4 9 7 5 3 1 4 9 1 3 4 9 7 5 3 1 4 9 1 5 0 4 4 9 7 5 3 1 4 9 1 2 4 8 5 0 Step 1: Multiply 3 by 7. The resulting product is 21. Write 1, and carry the 2. Step 3: Multiply 3 by 4. The resulting product is 12. Add the 2 that you carried to the 12, and obtain 14. Step 5: Multiply 5 by 7. The resulting product is 35. Write 5, and carry the 3. Step 7: Multiply 5 by 4. The resulting product is 20. Add the 4 that you carried to the 20, and obtain 24. 2 2 4 9 7 5 3 9 1 4 9 7 5 3 1 4 9 1 0 4 3 4 9 7 5 3 1 4 9 1 8 5 0 4 9 7 5 3 Step 2: Multiply 3 by 9. The resulting product is 27. Add the 2, which you carried, to the 27, and obtain 29. Write down 9, and carry the 2. Step 4: Place a 0 in the units place as in our next step we will be multiplying using the second digit (tens) Step 6: Multiply 5 by 9. The resulting product is 45. Add the 3, which you carried, to the 45, and obtain 48. Write down 8, and carry the 4. Step 8: Add to get the desired product. 1 4 9 1 2 4 8 5 0 2 6 3 4 1 NSSAL ©2013 47 Draft C. D. Pilmer Method 2: Multiplying Using the Expanded Form We first need to express the two numbers in their expanded forms (497 = 400 + 90 + 7 and 53 = 50 + 3) and then set the numbers up so that we can do the multiplication. 400 90 7 50 3 2 1 2 3 4 5 2 0 0 2 7 0 5 0 0 1 0 0 0 0 0 The 3 must be multiplied by the 400, 90, and 7. The 50 must be multiplied by the 400, 90, and 7. 2 6 3 4 1 Method 3: Lattice Method 4 9 7 4 5 3 2 4 0 1 5 7 2 5 5 2 1 3 6 2 2 2 1 7 3 9 4 3 0 1 5 2 5 2 2 3 1 1 7 4 1 We put the 497 along the top Multiply the numbers. (e.g. 4 Now ignore the 497 and 53 of the grid, and the 53 along times 5 is 20, 9 times 5 is 45, along the outside of our grid. the right side of the grid. etc.) Starting at the bottom, add the numbers along each diagonal placing the answer along the outer edge of the chart. If a sum exceeds 9, carry the tens digit up to the next diagonal. The numbers along the outside, starting at the upper left, represent the digits of your product. NSSAL ©2013 48 Draft C. D. Pilmer Example 3 Complete the following operation. 534 728 Answer: Method 1: Traditional Algorithm Method 2: Multiplying Using Expanded Form 500 30 4 700 20 8 5 3 4 7 2 8 4 2 7 2 1 0 6 8 0 3 7 3 8 0 0 3 4 0 8 0 0 0 0 0 2 4 0 3 8 8 7 5 2 6 0 8 0 0 1 0 2 2 1 3 5 0 2 0 0 0 0 0 0 0 0 3 8 8 7 5 2 Method 3: Lattice Method 5 3 2 2 3 5 1 1 4 3 8 2 8 2 8 8 8 6 2 0 7 0 0 0 1 4 3 4 2 3 5 NSSAL ©2013 0 1 0 5 1 0 8 3 4 0 49 8 6 2 4 7 2 1 2 2 Draft C. D. Pilmer Questions Complete the following operations without using a calculator, an addition facts chart, or a multiplication facts chart. Notice that we have included a few addition and subtraction questions. Show your work and use the method(s) you prefer. 1. (a) 46 39 (b) 74 63 (c) 86 45 (d) 57 41 (e) 83 56 (f) 65 28 (g) 435 14 (h) 542 36 (i) 348 65 NSSAL ©2013 50 Draft C. D. Pilmer (j) 368 92 (k) 647 84 (l) 915 83 (m) 142 263 (n) 852 273 (o) 621 364 (p) 748 459 (q) 937 291 (r) 602 237 NSSAL ©2013 51 Draft C. D. Pilmer 2. The banquet hall had 18 tables with 12 chairs at each. How many people can be seated at one time? 3. A landscaping company needs 89 cubic yards of topsoil at one site, and 134 cubic yards at another site. How many cubic yards do they need in total for the two sites? 4. A particular spreadsheet is comprised on 24 columns and 16 rows. How many entries can be placed on this spreadsheet? 5. The tank, when filled, held 530 litres of a particular chemical. After a period of time, 183 litres remained. How many litres of the chemical were used during that period of time? 6. With a reforestation project, they plant 350 seedlings every acre. If they wish to reforest 76 acres, how many seedlings will be needed? NSSAL ©2013 52 Draft C. D. Pilmer Dividing Multi-Digit Numbers In this section, we learn to divide multi-digit numbers by single digit numbers (e.g. 3759 6 ). We show two approaches (i.e. algorithms) to complete these types of questions; you choose the method you prefer. We will not be dividing a multi-digit number by another multi-digit number (e.g. 5768 74 ). Our rationale is that these latter types of question are tedious and best solved using a calculator. Example 1 Solve 2856 8 Answer: Method 1: Traditional Algorithm This is the technique that many people have worked with in the past, however, many individuals struggle to understand why this technique works. That is why we generally suggest that you learn method 2, which generally makes more sense. ? 8 2856 3 8 2856 24 3 8 2856 Ask: "How many times does 8 divide into 2?" Answer: It does not go into it, therefore we move to the next step where we include the next place value. Ask: "How many times does 8 divide into 28?" Answer: We estimate 3 times. Place 3 in the hundreds column, multiply 8 by 3, and place the answer 24 below the 28. Subtract the 24 from the 28. Following this, bring down the 5 from the tens position. - 24 45 35 8 2856 - 24 45 40 35 8 2856 Ask: "How many times does 8 divide into 45?" Answer: We estimate 5 times. Place 5 in the tens column, multiply 8 by 5, and place the answer 40 below the 45. Subtract the 40 from the 45. Following this, bring down the 6 from the units position. - 24 45 - 40 56 NSSAL ©2013 53 Draft C. D. Pilmer 357 Ask: "How many times does 8 divide into 56?" Answer: 7 times. Place 7 in the units column, multiply 8 by 7, and place the answer 56 below the 56. 8 2856 - 24 45 - 40 56 56 Subtract the 56 from the 56. There is no remainder, therefore we know that 8 divides evenly into 2856. 357 8 2856 - 24 45 - 40 56 - 56 0 Method 2: Partial Quotient Method 8 2856 1600 8 2856 1600 1256 8 2856 1600 1256 800 8 2856 1600 1256 800 456 NSSAL ©2013 200 How many times does 8 go into 1600? This learner goes with 200 because he/she knows that 8 times 200 is 1600. (The learner could have gone with a larger number like 300, but it does not matter with this method.) Now he/she subtracted 1600 from 2856. 200 200 How many times does 8 go into 1256. This learner goes with 100 because he/she knows that 8 times 100 is 800. 100 Now he/she subtracted 800 from 1256. 200 100 54 Draft C. D. Pilmer 8 2856 1600 1256 800 456 400 8 2856 1600 1256 800 456 400 56 8 2856 1600 1256 800 456 400 56 56 0 357 8 2856 1600 1256 800 456 400 56 56 0 NSSAL ©2013 200 How many times does 8 go into 456. This learner goes with 50 because he/she knows that 8 times 50 is 400. 100 50 Now he/she subtracted 400 from 456. 200 100 50 200 How many times does 8 go into 56. This learner goes with 7 because he/she knows that8 times 7 is 56. After we filled in the 56, we did the subtraction and found that we had a remainder of 0. That means 8 divides evenly into 2856. 100 50 7 In our last step the learner simply adds 200, 100, 50, and 7. That means that the quotient is 357. 200 2856 8 = 357 100 50 7 55 Draft C. D. Pilmer Example 2 Solve 4785 7 Answer: Method 1: Traditional Algorithm 683 R:4 7 4785 - 42 58 - 56 25 - 21 4 Method 2: Partial Quotient Method We have shown you three solutions to this question. The first student was the most efficient because he/she did the question in the fewest number of steps, however, all of the students have correct answers. That is the great thing about the partial quotient method; there is more than one way to do it right. In this case, 7 does not go evenly into 4785; we have a remainder of 4 when we complete the division. First Learner: 683 R: 4 7 4785 4200 585 560 25 21 4 NSSAL ©2013 600 80 3 Second Learner: 683 R: 4 7 4785 400 2800 1985 1400 585 560 25 21 4 200 80 3 56 Third Learner: 683 R: 4 7 4785 4200 600 585 350 50 235 210 30 25 21 4 3 Draft C. D. Pilmer Example 3 Solve 31 654 9 Answer: Method 1: Traditional Algorithm 3517 R:1 9 31654 - 27 46 - 45 15 - 9 64 - 63 1 Method 2: Partial Quotient Method We have again supplied multiple solutions; all of them are correct. First Learner 3517 R: 1 9 31654 27000 4654 4500 154 90 64 63 1 3000 500 10 7 Second Learner: 3517 R: 1 9 31654 18000 2000 13654 9000 1000 4654 400 3600 1054 900 154 90 64 63 1 100 10 Third Learner: 3517 R: 1 9 31654 27000 3000 4654 4500 500 154 90 64 45 19 18 1 10 5 2 7 We have a video on YouTube that explains the partial quotient method. Google search "YouTube Long Division Partial Quotient Method nsccalpmath." NSSAL ©2013 57 Draft C. D. Pilmer Questions Complete the following operations without using a calculator, an addition facts chart, or a multiplication facts chart. Notice that we have included a few addition, subtraction, and multiplication questions. Show your work and use the method(s) you prefer. 1. (a) 268 4 (d) 54 83 NSSAL ©2013 (b) 178 3 (c) 2538 6 (e) 3270 4 (f) 825 467 58 Draft C. D. Pilmer (g) 2919 5 (h) 5646 9 (i) 2474 653 (j) 6259 6 (k) 392 79 (l) 26194 7 NSSAL ©2013 59 Draft C. D. Pilmer 2. The prize money of $4710 had to be shared equally by the 6 ticket holders. How much did it person receive? 3. A particular car holds 38 litres of gasoline and travels 14 kilometres per litre. How far can the car travel on a full tank of gasoline? 4. The land developer wants to take her 234 acre property and break it into 9 lots of equal size. What will be the acreage of these new lots? 5. Tylena earned $2860 this month and her expenses during that same period were $2395. How much could Tylena potentially save during this month? 6. You are selling lemonade at the fair. You large dispensing container holds 192 ounces of lemonade. If you are serving the drinks in 6 ounce cups, how many cups can you potentially sell? NSSAL ©2013 60 Draft C. D. Pilmer Appendix NSSAL ©2013 61 Draft C. D. Pilmer Connect Four Whole Number Addition Game (A) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Addend Strip whose sum is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate sum. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same sum but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Addend Strip. They then mark the square with that sum using a O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the addend strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 10 12 7 13 8 11 9 11 10 12 6 13 6 14 9 11 10 9 8 11 12 7 14 11 13 10 8 6 9 10 9 7 14 10 12 8 6 7 Addend Strip: 3 NSSAL ©2013 4 5 62 Draft C. D. Pilmer Connect Four Whole Number Addition Game (B) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Addend Strip whose sum is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate sum. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same sum but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Addend Strip. They then mark the square with that sum using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the addend strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 12 11 18 14 16 14 15 14 13 16 12 13 16 12 15 10 14 17 15 17 14 18 15 13 13 10 13 16 11 18 15 12 11 17 14 10 Addend Strip: 5 NSSAL ©2013 6 7 8 9 63 Draft C. D. Pilmer Connect Four Whole Number Subtraction Game (A) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers; one from Value 1 and one from Value 2. Once they have chosen the two numbers, they can capture one square with that appropriate difference (i.e. Value 1 subtract Value 2). They either mark the square with an X or place a colored counter on the square. There may be other squares with that same difference but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips. They then mark the square with that difference using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 3 2 5 4 6 4 7 4 6 2 3 5 6 0 1 0 5 6 3 5 3 7 2 4 4 3 2 4 1 0 1 7 0 5 3 6 Value 1: 13 NSSAL ©2013 Value 2: 12 11 10 9 6 64 7 8 9 Draft C. D. Pilmer Connect Four Whole Number Subtraction Game (B) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers; one from Value 1 and one from Value 2. Once they have chosen the two numbers, they can capture one square with that appropriate difference (i.e. Value 1 subtract Value 2). They either mark the square with an X or place a colored counter on the square. There may be other squares with that same difference but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips. They then mark the square with that difference using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 3 5 4 5 6 5 6 8 7 9 10 7 9 7 6 3 5 9 7 10 5 7 8 4 8 6 9 4 9 3 4 7 8 10 5 6 Value 1: 15 NSSAL ©2013 Value 2: 14 13 12 5 65 6 7 8 9 Draft C. D. Pilmer Connect Four Whole Number Multiplication Game (A) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Factor Strip whose product is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate product. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same product but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Factor Strip. They then mark the square with that product using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the fraction strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 6 45 27 5 45 8 10 0 36 18 20 15 36 8 12 4 0 36 2 18 45 27 6 12 20 4 15 0 10 9 27 12 3 6 36 20 Factor Strip: 0 NSSAL ©2013 1 2 3 4 66 5 9 Draft C. D. Pilmer Connect Four Whole Number Multiplication Game (B) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Factor Strip whose product is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate product. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same product but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Factor Strip. They then mark the square with that product using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the fraction strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 18 2 30 8 12 24 9 54 12 18 10 6 24 5 8 6 54 20 10 30 18 5 24 3 24 4 20 12 2 18 12 54 9 30 5 8 Factor Strip: 1 NSSAL ©2013 2 3 4 5 67 6 9 Draft C. D. Pilmer Connect Four Whole Number Multiplication Game (C) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Factor Strip whose product is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate product. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same product but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Factor Strip. They then mark the square with that product using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the fraction strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 14 63 6 28 15 30 42 12 30 63 14 10 8 21 54 18 54 21 35 15 8 28 42 12 18 54 14 63 6 35 10 28 42 12 21 18 Factor Strip: 2 NSSAL ©2013 3 4 5 6 68 7 9 Draft C. D. Pilmer Connect Four Whole Number Multiplication Game (D) Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers on the Factor Strip whose product is that desired square. Once they have chosen the two numbers, they can capture one square with that appropriate product. They either mark the square with an X or place a colored counter on the square. There may be other squares with that same product but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips on the Factor Strip. They then mark the square with that product using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved on the fraction strip in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 42 12 16 8 24 48 6 72 45 54 15 18 56 24 21 16 56 20 14 30 10 40 6 27 54 18 36 12 42 21 15 72 27 14 35 10 5 6 Factor Strip: 2 NSSAL ©2013 3 4 69 7 8 9 Draft C. D. Pilmer Connect Four Whole Number Division Game Number of Players: Two Objective: The winner is the first player to connect four of his/her pieces horizontally, vertically or diagonally. Instructions: 1. Roll a die to see which player will go first. 2. The first player looks at the board and decides which square he/she wishes to capture. They place two paperclips on two numbers; one from Value 1 and one from Value 2. Once they have chosen the two numbers, they can capture one square with that appropriate quotient (i.e. Value 1 divided by Value 2). They either mark the square with an X or place a colored counter on the square. There may be other squares with that same quotient but only one square can be captured at a time. 3. Now the second player is ready to capture a square but he/she can only move one of the paperclips. They then mark the square with that quotient using an O or a different colored marker. If a player cannot move a single paperclip to capture a square, a paperclip must still be moved in order to ensure that the game can continue. 4. Play alternates until one player connects four squares. Remember that only one paperclip is moved at a time. If none of the players is able to connect four, then the winner is the individual who has captured the most squares. Game Board: 6 24 12 15 12 2 8 3 6 30 4 15 18 12 10 9 8 12 6 8 2 24 6 9 30 4 15 12 4 3 6 18 9 2 10 18 Value 1: 30 NSSAL ©2013 Value 2: 24 18 12 6 1 70 2 3 Draft C. D. Pilmer Flash Cards: Addition Remove the following pages, cut out the flash cards, and regularly practice your math fact using these cards. NSSAL ©2013 30 + 20 400 + 300 2 000 + 5 000 40 + 50 100 + 600 3 000 + 6 000 60 + 70 500 + 800 8 000 + 4 000 90 + 30 700 + 400 1 000 + 2 000 10 + 80 200 + 900 9 000 + 5 000 70 + 70 800 + 800 6 000 + 6 000 60 + 40 300 + 700 2 000 + 8 000 71 Draft C. D. Pilmer NSSAL ©2013 7 000 700 50 9 000 700 90 12 000 1 300 130 3 000 1 100 120 14 000 1 100 90 12 000 1 600 140 10 000 1 000 100 72 Draft C. D. Pilmer NSSAL ©2013 20 + 20 900 + 400 2 000 + 3 000 80 + 70 700 + 800 9 000 + 9 000 30 + 50 300 + 100 4 000 + 3 000 90 + 80 200 + 400 5 000 + 8 000 10 + 60 500 + 700 6 000 + 2 000 20 + 40 100 + 900 7 000 + 7 000 60 + 60 600 + 800 8 000 + 6 000 73 Draft C. D. Pilmer NSSAL ©2013 5 000 1 300 40 18 000 1 500 150 7 000 400 80 13 000 600 170 8 000 1 200 70 14 000 1 000 60 14 000 1 400 120 74 Draft C. D. Pilmer Flash Cards: Subtraction Remove the following pages, cut out the flash cards, and regularly practice your math fact using these cards. NSSAL ©2013 50 - 10 600 - 300 3 000 - 1 000 80 - 30 500 - 400 7 000 - 4 000 90 - 20 900 - 300 9 000 - 5 000 40 - 40 700 - 100 8 000 - 7 000 30 - 10 800 - 800 6 000 - 4 000 90 - 50 900 - 500 9 000 - 6 000 80 - 70 300 - 200 5 000 - 5 000 75 Draft C. D. Pilmer NSSAL ©2013 2 000 300 40 3 000 100 50 4 000 600 70 1 000 600 0 2 000 0 20 3 000 400 40 0 100 10 76 Draft C. D. Pilmer 100 - 60 1 200 - 700 13 000 - 8 000 120 - 50 1 100 - 900 16 000 - 9 000 140 - 60 1 700 - 800 11 000 - 3 000 150 - 90 1 500 - 600 15 000 - 7 000 110 - 70 1 600 - 800 12 000 - 6 000 160 - 80 1 300 - 400 18 000 - 9 000 120 - 50 1 400 - 800 14 000 - 6 000 NSSAL ©2013 77 Draft C. D. Pilmer NSSAL ©2013 5 000 500 40 7 000 200 70 8 000 900 80 8 000 900 60 6 000 800 40 9 000 900 80 8 000 600 70 78 Draft C. D. Pilmer Flash Cards: Multiplication Remove the following pages, cut out the flash cards, and regularly practice your math fact using these cards. NSSAL ©2013 2 × 40 70 × 30 60 × 200 30 × 5 4 × 600 1000 × 8 80 × 6 80 × 80 7 × 3000 7 × 70 50 × 10 400 × 30 40 × 7 200 × 9 2000 × 9 9 × 50 3 × 500 40 × 700 60 × 3 60 × 30 6 × 6000 79 Draft C. D. Pilmer NSSAL ©2013 12 000 2 100 80 8 000 2 400 150 21 000 6 400 480 12 000 500 490 18 000 1 800 280 28 000 1 500 450 36 000 1 800 180 80 Draft C. D. Pilmer NSSAL ©2013 8 × 60 70 × 70 30 × 900 70 × 5 300 × 8 4 × 8000 30 × 9 5 × 500 500 × 30 8 × 70 30 × 90 1000 × 7 90 × 4 60 × 80 800 × 60 3 × 40 900 × 9 90 × 700 20 × 7 7 × 600 20 × 800 81 Draft C. D. Pilmer NSSAL ©2013 27 000 4 900 480 32 000 2 400 350 15 000 2 500 270 7 000 2 700 560 48 000 4 800 360 63 000 8 100 120 16 000 4 200 140 82 Draft C. D. Pilmer Flash Cards: Division Remove the following pages, cut out the flash cards, and regularly practice your math fact using these cards. NSSAL ©2013 80 2 90 30 2 100 7 50 5 180 90 1 600 40 160 8 270 30 2 400 300 120 4 320 80 5 400 9 350 7 420 70 4 900 70 480 6 250 50 3 200 400 630 9 720 90 8 100 900 83 Draft C. D. Pilmer NSSAL ©2013 300 3 40 40 2 10 6 9 20 600 4 30 70 6 50 8 5 80 9 8 70 84 Draft C. D. Pilmer Answers Introduction to Whole Numbers (pages 1 to 6) 1. (a) nine hundred eighty-six (b) four hundred twelve (c) two thousand, three hundred ninety-seven (d) four thousand, six hundred nine (e) twelve thousand, seven hundred fifty (f) three hundred forty-seven thousand, fifty-two (g) five hundred six thousand, nine hundred (h) two million, eight hundred seventy thousand, forty (i) three hundred fifty million, twenty-six thousand (j) seventeen million, five hundred nine thousand, one hundred (k) seven billion, three hundred sixty million, eight hundred thousand (l) eleven billion, ninety-four million, three hundred thousand, two (m) six trillion, five hundred thirty-two billion, eighty 2. (a) (b) (c) (d) (e) (f) (g) (h) (i) (j) 6 742 3 126 511 809 327 13 052 071 63 147 408 700 260 349 008 2 910 706 050 162 083 400 000 80 307 005 200 3. (a) (b) (c) (d) (e) millions place hundred millions place ten thousands place ten billions place hundred thousands place 4. (a) (b) (c) (d) (e) 4 296 4000 200 90 6 136 942 100 000 30 000 6 000 900 40 2 6 056 730 6 000 000 50 000 6 000 700 30 45 760 500 40 000 000 5 000 000 700 000 60 000 500 9 602 000 000 9 000 000 000 600 000 000 2 000 000 5. (a) 3, 9, 52, 93, 546, 800 (b) 27, 29, 529, 546, 8 698, 8 700 (c) 790, 796, 9 360, 9 502, 33 870, 34 000 (d) 38 099, 38 500, 56 899, 56 943, 76 000, 102 000 NSSAL ©2013 85 Draft C. D. Pilmer 6. (a) (b) (c) (d) (e) (f) (g) (h) (i) Average Canadian Mortgage in 2013 Province of Nova Scotia's Debt in 2012 Approximate Cost of a New Family Sedan Approximate Cost of a 42 inch Flat Screen TV Overall Cost of 3 Year Phone Plan with Data Package Average Individual Income of Nova Scotian in 2010 Canada's Federal Debt in 2012 Cost of Purchasing a Tim Hortons' Franchise in 2012 Estimated Cost of New Halifax Convention Center 7. (h) (e) (b) (f) (a) (g) (i) (d) (c) $500 000 $2200 $14 000 000 000 $40 000 $245 000 $600 000 000 000 $159 000 000 $500 $26 000 Number (a) What whole number is after 325? 326 (b) What whole number is before 6 421? 6 420 (c) What whole number is between 45 188 and 45 190? 45 189 (d) What whole numbers are between 763 and 768? (e) What whole number is after 7 239? 7 240 (f) What whole number is between 9 398 and 9400? 9 399 (g) What whole number is before 82 600? 82 599 (h) What whole number is between 62 985 and 62 987? 62 986 (i) What whole numbers are between 69 997 and 70 000? (j) What whole number is before 120 000? (k) What whole number is before 7 300 000? (l) What whole numbers are between 27 029 and 27 032? 764, 765, 766, 767 69 998, 69 999 119 999 7 299 999 27 030, 27 031 (m) What whole number is after 15 999? 16 000 (n) What whole number is between 386 638 and 386 640? 386 639 (o) What whole numbers are between 9 997 and 10 001? 9 998, 9 999, 10 000 (p) What whole number is before 430 000 000? (q) What whole number is after 549 999? 550 000 (r) What whole number is between 31 652 and 31 654? 31 653 (s) What whole numbers are between 72 999 and 73 002? NSSAL ©2013 86 429 999 999 73 000, 73 001 Draft C. D. Pilmer Math Facts: Addition and Multiplication (pages 7 to 16) 1. (a) 10 (d) 8 (g) 8 (j) 14 (m) 10 (p) 12 (s) 11 (v) 13 (y) 8 (b) 6 (e) 7 (h) 16 (k) 9 (n) 12 (q) 13 (t) 5 (w) 9 (z) 8 (c) (f) (i) (l) (o) (r) (u) (x) 12 9 9 11 2 11 13 4 2. (a) 8 (d) 0 (g) 12 (j) 12 (m) 48 (p) 20 (s) 16 (v) 36 (y) 45 (b) 35 (e) 27 (h) 49 (k) 5 (n) 24 (q) 21 (t) 18 (w) 63 (z) 56 (c) (f) (i) (l) (o) (r) (u) (x) 8 28 0 72 54 64 30 18 (b) 5 and 7 (e) 3 and 10 (c) 1 and 3 (f) 3 and 8 3. (a) (b) (c) (d) (e) (f) (g) (h) addition addition multiplication addition multiplication multiplication addition multiplication 4. (a) 2 and 3 (d) 2 and 8 5. (a) NSSAL ©2013 (b) 4 2 3 5 6 4 3 4 2 4 5 6 2 3 4 6 4 5 87 Draft C. D. Pilmer (c) (d) 5 7 6 8 7 9 7 6 5 9 8 7 6 5 7 7 9 8 (e) (f) 3 5 4 2 8 6 7 9 5 2 3 4 9 7 6 8 2 4 5 3 7 8 9 6 4 3 2 5 6 9 8 7 Fact Families (pages 17 to 21) 1. (a) 5 9 14 14 9 5 14 5 9 (b) 7 4 28 28 7 4 28 4 7 2. (a) 4 8 12 8 4 12 12 4 8 12 8 4 (b) 7 9 63 9 7 63 63 9 7 63 7 9 (e) 6 7 13 7 6 13 13 7 6 13 6 7 (d) 8 3 24 3 8 24 24 8 3 24 3 8 NSSAL ©2013 88 Draft C. D. Pilmer (f) 15 6 9 15 9 6 6 9 15 9 6 15 (g) 10 2 5 10 5 2 2 5 10 5 2 10 3. (a) 8 (d) 1 (g) 0 (j) 5 (m) 8 (p) 0 (s) 5 (v) 2 (y) 3 (b) 5 (e) 5 (h) 7 (k) 7 (n) 3 (q) 8 (t) 8 (w) 8 (z) 2 (c) (f) (i) (l) (o) (r) (u) (x) 6 7 10 4 7 9 3 7 4. (a) 7 (d) 8 (g) 2 (j) 4 (m) 5 (p) 8 (s) 5 (v) 9 (y) 8 (b) 3 (e) 1 (h) 5 (k) 7 (n) 9 (q) 6 (t) 6 (w) 3 (z) 6 (c) (f) (i) (l) (o) (r) (u) (x) 6 5 3 4 2 8 7 1 5. (a) 5 (d) 14 (g) 9 (j) 7 (m) 9 (p) 10 (s) 1 (v) 0 (b) 9 (e) 24 (h) 9 (k) 13 (n) 6 (q) 32 (t) 14 (w) 0 (c) (f) (i) (l) (o) (r) (u) (x) 15 7 16 9 6 7 6 1 6. (a) (d) (g) (j) (b) (e) (h) (k) (c) (f) (i) (l) 4&7 5&8 9&4 5&5 3&5 12 & 1 4&4 2&6 7. (a) 5 & 7 (d) 1 & 9 (g) 8 & 3 NSSAL ©2013 2 & 10 6&3 6&4 10 & 1 (b) 2 & 5 (e) 4 & 4 (h) 0 & 2 (c) 3 & 4 (f) 2 & 9 (i) 2 & 10 89 Draft C. D. Pilmer 9. (a) (b) 6 6 = 1 = 14 - 13 18 9 = 2 = 2 1 - - + - 5 3 10 7 8 14 1 2 6 3 = = = = = = = = = = 5 32 30 3 = 10 = 2 8 = 4 = 12 3 = = = = = = = = = = 31 24 1 6 15 40 0 3 3 9 - + - + + 3 8 1 10. (a) (b) (c) (d) (e) (f) + 8 = 9 = 3 8 = (c) (f) (i) (l) (o) (r) (u) (x) 15 8 8 17 0 72 4 29 1 = 4 - 3 division multiplication subtraction addition subtraction division Order of Operations (pages 22 to 25) 1. (a) 4 (d) 11 (g) 30 (j) 26 (m) 28 (p) 59 (s) 7 (v) 23 (b) 23 (e) 14 (h) 13 (k) 1 (n) 44 (q) 26 (t) 1 (w) 3 2. Answers will vary. Multiples of Ten, One Hundred and One Thousand (pages 26 to 32) 1. (a) (d) (g) (j) 80 8000 150 1400 NSSAL ©2013 (b) (e) (h) (k) 900 900 1100 11000 (c) (f) (i) (l) 90 120 9000 80 1600 Draft C. D. Pilmer 2. (a) (d) (g) (j) 30 600 700 70 (b) (e) (h) (k) 400 4000 80 800 (c) (f) (i) (l) 0 20 9000 7000 3. (a) (d) (g) (j) 210 36000 24000 350 (b) (e) (h) (k) 1500 4800 8100 42000 (c) (f) (i) (l) 16000 250 2400 8000 4. (a) 40 (d) 90 (g) 300 (j) 80 (m) 800 (p) 70 (b) (e) (h) (k) (n) (q) 4 9 8 70 2 5 (c) (f) (i) (l) (o) (r) 7 70 2 500 60 600 5. (a) 1400 (d) 110 (g) 600 (j) 1600 (m) 1300 (p) 80 (s) 70 (b) (e) (h) (k) (n) (q) (t) 50 10 1300 3 400 56000 3200 (c) (f) (i) (l) (o) (r) (u) 500 270 5000 14000 70 40 9 6. (a) 20 & 40 (d) 90 & 90 (g) 30 & 60 (b) 30 & 40 (e) 60 & 90 (h) 60 & 70 7. (a) 10, 20, 30 Puzzle NSSAL ©2013 (c) 50 & 70 (f) 20 & 80 (i) 40 & 90 (b) 20, 30, 40 Puzzle 20 10 30 20 30 40 30 20 10 40 20 30 10 30 20 30 40 20 91 Draft C. D. Pilmer (c) 30, 40, 50 Puzzle (d) 40, 50, 60 Puzzle 50 40 30 50 40 60 30 50 40 60 50 40 40 30 50 40 60 50 (e) 50, 60, 70 Puzzle (f) 70, 80, 90 Puzzle 70 60 50 80 90 70 50 70 60 90 70 80 60 50 70 70 80 90 30 = 8. (a) 3 90 = 40 + 50 - - + - 60 27 30 0 30 = = = = = 180 3 = 60 = 40 + 20 = = = = = 20 24 2 240 4 - 9 NSSAL ©2013 + 21 = 30 = 6 92 5 Draft C. D. Pilmer (b) 70 20 = 1400 = 200 + 1200 - + - 40 20 200 100 2 = = = = = 30 40 = 1200 = 2 600 = = = = = 0 4 900 7 10 + + - 30 10 = 300 = 5 60 Divisibility and Prime (pages 33 and 34) 1. 2 (a) 22 (c) 13 (e) 75 (g) 90 (i) 61 (k) 261 (m) 428 (o) 417 (q) 510 (s) 8001 (u) 3218 (w) 2870 (y) 2853 3 5 6 P 2 (b) 55 (d) 72 (f) 29 (h) 63 (j) 86 (l) 440 (n) 546 (p) 948 (r) 179 (t) 4315 (v) 5202 (x) 1320 (z) 7302 3 5 6 P 2. Answers will vary. NSSAL ©2013 93 Draft C. D. Pilmer Estimating (pages 35 to 37) 1. (a) (b) (c) (d) (e) (f) (g) (h) unreasonable reasonable reasonable unreasonable reasonable unreasonable unreasonable reasonable 2. (a) (b) (c) (d) (e) (f) (g) 1 4 9 2 3 4 8 Adding Multi-Digit Numbers (pages 38 to 40) 1. (a) (d) (g) (j) 88 759 800 5 185 2. (a) 172 (b) (e) (h) (k) 84 672 934 14 208 (c) (f) (i) (l) (b) 610 136 1 485 1 437 15 760 (c) 1286 3. 251 people Subtracting Multi-Digit Numbers (pages 41 to 44) 1. (a) 25 (d) 127 (g) 1 054 (j) 1 245 (m) 6 334 (b) (e) (h) (k) (n) 57 380 226 3 860 11 437 2. (a) 616 (b) 1 156 (c) (f) (i) (l) (o) 153 187 126 4 168 771 (c) 4 867 3. $883 4. $213 NSSAL ©2013 94 Draft C. D. Pilmer 5. 164 people Multiplying Multi-Digit Numbers (pages 45 to 52) 1. (a) 1 794 (d) 2 337 (g) 6 090 (j) 33 856 (m) 37 346 (p) 343 332 (b) (e) (h) (k) (n) (q) 4 662 27 19 512 731 1 125 272 667 (c) (f) (i) (l) (o) (r) 131 1 820 283 75 945 226 044 365 (c) (f) (i) (l) 423 358 3 127 3742 2. 216 people 3. 223 cubic yards 4. 384 entries 5. 347 litres 6. 26 600 seedlings Dividing Multi-Digit Numbers (pages 53 to 60) 1. (a) (d) (g) (j) 67 4482 583 R: 4 1 043 R: 1 (b) (e) (h) (k) 59 R: 1 817 R: 2 627 R: 3 30 968 2. $785 3. 532 kilometres 4. 26 acres 5. $465 6. 32 cups NSSAL ©2013 95 Draft C. D. Pilmer
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