MSM07G6_RESBK_Ch01_028_035.pe
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Page 33
Name
LESSON
Date
Class
Problem Solving
1-4 Order of Operations
Evaluate each expression to complete the table.
Mammals with the Longest Tails
Mammal
Expression
Tail Length
2 32 7 (10 4)
59
5 6 52
55
1.
Asian elephant
2.
Leopard
3.
African elephant
6 (72 8) 3
51
4.
African buffalo
51 62 9 12
43
5.
Giraffe
43 3 7
43
6.
Red kangaroo
11 48 6 4
43
Choose the letter for the best answer.
8. An elephant eats about 500 pounds
of grass and leaves every day. There
are 2 Africa elephants and 3 Asian
elephants living in the City Zoo. How
many pounds of grass and leaves do
the zookeepers need to order each
week to feed all the elephants?
F 2,500 pounds
G 17,500 pounds
嘷
7. Adam and his two brothers went to
the zoo. Each ticket to enter the zoo
costs $7. Adam bought two bags of
peanuts for $4 each, and one of his
brothers bought a lion poster for $12.
Which expression shows how much
money they spent at the zoo in all?
A 7 4 12
B 7 3 4 12
C 7 3 4 2 12
嘷
H 3,000 pounds
J 21,000 pounds
D (7 3) (4 12)
10. Some kangaroos can cover 30 feet in
a single jump! If a kangaroo could
jump like that 150 times in a row,
how much farther would it need to go
to cover a mile? (1 mile 5,280 feet)
H 176 feet
F 780 feet
嘷
9. The average giraffe is 18 feet tall.
Which of these expressions shows
the height of a giraffe?
A 42 2
B 3 12 4 2
C 33 9 6
嘷
G 26 feet
D 20 5 5 6
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
33
J 5,100 feet
Holt Mathematics
Challenge
1-4 Crack the Expression Code
Reteach
1-4 Order of Operations
LESSON
LESSON
Each of these symbols stands for a different operation symbol:
A mathematical phrase that includes only numbers and operations
is called a numerical expression.
9 8 3 6 is a numerical expression.
Each of these animals stands for a different whole number 1–4:
To evaluate a numerical expression, you find its value.
You can use the order of operations to evaluate a numerical
expression.
Order of Operations
1. Do all operations within parentheses.
2. Find the values of numbers with exponents.
3. Multiply and divide in order from left to right.
4. Add and subtract in order from left to right.
Use the equations below to find what each symbol and animal
represents in the expression code.
Evaluate the expression.
60 (7 3) 32
60 10 32
Do all operations within parentheses.
60 10 9
Find the values of numbers with exponents.
69
Multiply and divide in order from left to right.
15
Add and subtract in order from left to right.
7
Evaluate each expression.
1. 7 (12 8) – 6
7
140
20
–6
2. 10 (12 34) 3
46
10 460
–6
40
463
9. (33 10) – 2
5
31
Holt Mathematics
Expression
Tail Length
2 32 7 (10 4)
59
5 6 52
55
African elephant
6 (72 8) 3
51
African buffalo
51 62 9 12
43
43 3 7
43
11 48 6 4
43
4.
5.
Giraffe
6.
Red kangaroo
7.
1
8.
3
4
6.
2
32
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
When you read a sentence, you read each word in order from left to
right. To evaluate an expression, you cannot always compute the
operations in the order they are given, from left to right. You must
follow the order of operations. The order is listed in the flowchart
below:
Mammals with the Longest Tails
3.
5.
Reading Strategies
1-4 Use a Flowchart
Mammal
Leopard
LESSON
Evaluate each expression to complete the table.
2.
3.
4.
Problem Solving
1-4 Order of Operations
Asian elephant
2.
35
LESSON
1.
NUMBERS
1.
–7
97
8. 3 (12 4) 22
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
OPERATIONS
–7
6. 36 4 11 8
46
18
30
33
5. 7 3 (8 5)
14
7. 52 (2 8) 9
10 3
134
4. 23 (10 – 4)
3
3. 10 (6 5) – 7
Parentheses
Example
3 (5 4) 22
Exponents
394
Multiply or divide (left to right)
27 4
8. An elephant eats about 500 pounds
of grass and leaves every day. There
are 2 Africa elephants and 3 Asian
elephants living in the City Zoo. How
many pounds of grass and leaves do
the zookeepers need to order each
week to feed all the elephants?
F 2,500 pounds
G 17,500 pounds
7. Adam and his two brothers went to
the zoo. Each ticket to enter the zoo
costs $7. Adam bought two bags of
peanuts for $4 each, and one of his
brothers bought a lion poster for $12.
Which expression shows how much
money they spent at the zoo in all?
A 7 4 12
B 7 3 4 12
C 7 3 4 2 12
D (7 3) (4 12)
23
1. Write a flowchart to list the order in which you would compute
the operations for this expression: 12 2 3 8 2.
Multiply
G 26 feet
Divide
Subtract
Add
2. Evaluate this expression: 12 2 3 8 2.
10
3. Write a flowchart to list the order in which you would compute
the operations for this expression: (12 2) 3 8 2.
10. Some kangaroos can cover 30 feet in
a single jump! If a kangaroo could
jump like that 150 times in a row,
how much farther would it need to go
to cover a mile? (1 mile 5,280 feet)
H 176 feet
F 780 feet
D 20 5 5 6
Add or subtract (left to right)
Answer each question.
H 3,000 pounds
J 21,000 pounds
9. The average giraffe is 18 feet tall.
Which of these expressions shows
the height of a giraffe?
A 42 2
B 3 12 4 2
C 33 9 6
Add or subtract
from left to right
Parentheses
3 9 22
Choose the letter for the best answer.
Multiply or divide
from left to right
Exponents
Parentheses
Multiply
Divide
Add
4. Evaluate this expression: (12 2) 3 8 2.
34
5. Explain how Exercises 1 and 3 are alike and how they are
different.
J 5,100 feet
Possible explanation: The numbers and operations in each
expression are the same, but the value of each expression
is different since Exercise 3 includes parentheses.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
33
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
Holt Mathematics
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
70
34
Holt Mathematics
Holt Mathematics