TOPIC
18
Strand:
Strand unit:
516.3 Solve problems involving the operations with decimals.
551
Compare value for money using the unitary method.
1. Renaming amounts of money as euro or cent and recording using the €
symbol and decimal point.
2. Solving and completing practical 1-step and 2-step problems and tasks
involving the addition, subtraction, multiplication and simple division of money.
1. Applying and problem-solving: Selecting appropriate mathematical processes to solve
problems involving money, use the concept of unitary method in a variety of contexts.
2. Integrating and connecting: Recognising the use of the unitary method in everyday situations
understanding the connection between the unitary method and the mathematical processes
used.
3. Implementing: Using mental procedures for carrying out mathematical tasks involving money,
executing the procedures to implement the unitary method.
4. Understanding and recalling: Multiplication and division facts, euro notes and coins.
Coins, notes, bank statements, receipts, calculators
Notes, coins, euro, value for money, unitary method, cheapest, expensive, sale.
1. Review finding a fraction or decimal fraction of an amount.
2. Review all euro notes and coins. Practice renaming amounts with and without
the € sign.
3. Review rounding and estimation to assist students with putting the decimal
point in the correct place.
4. Students often find the unitary method difficult when used in conjunction with the units of
measurement in length, weight and capacity.
76
Target board 7:
Read each number as euro and cents.
Fans:
Oranges cost 15 cent each how much for 5?
A bag of 10 apples cost €2.00. How much for each apple? Vary simple sums like this.
What change would I get from €10 euro if I spent €5.50, €7.30, etc?
What is 25% of €200, what is 10% of €450 etc?
Loop game:
Money
1. Examining amounts of pocket money received in the class. Calculate the average received.
Analyse the products and services that pocket money is used for.
2. You won €10,000 and you have to spend it all in 1 day. List the products and services that you
would buy. How much would you have left from the €10,000?
3. What is a mint? What coins were used in Ireland before the decimal system and before the
euro?
4. Currencies: What currency is used in the United States, Canada, Mexico, Brazil, Argentina,
Spain, Italy, Denmark, Sweden, Russia, China, Japan, South Africa, Kenya, Australia and New
Zealand?
5. Exchange rates: How much is €1 in different currencies? Is it worth more or less than this time
last week/last month/last year? Why do currencies fluctuate?
Find the correct answer:
1. This is the change from €10 when I bought a book for €4·77. (€5·23)
2. This amount is 50% of €1. (50c)
3. This amount is €8·70 less than €10. (€1·30)
4. This amount is 0·7 of €100. (€70)
5. This amount is the change from €60 when I bought a computer game for €30·33. (€29·67)
6. 99c is _____% of _____. (10% of €9·90)
7. €2·50 is 1/__ of 10. (1/4 of €10)
8. €36·45 is _____ of _____. (0·45 of €81)
9. This amount is €3·55 more than €10. (€13·55)
Lower attainers:
Extra practice on unitary method and converting cent to euro and euro to cent.
77
Higher attainers:
1. Word problems involving money.
2. Activity C on page 115 and Activity B on page 116 may prove challenging.
Topic
Topic
18
18
1. (a) 6 apples got 96c. How much for
1. Write the following amounts using the € sign.
(a) 2c
(b) 17c
(c) 103c
(d) 250c
(e) 1000c
(f) 2550c
(g) 20000c
(h) 32575c
(i) 12 apples?
(ii) 15 apples?
(b) 10 pens cost €1.99. How much for
(i) 2 pens?
(ii) 12 pens?
2. Write the following amounts as cent.
(a) €0.05
(b) €0.33
(c) €2.68
(d) €9.99
(c) 9 fruit bars cost €1.99. How much for 18 fruit bars?
(d) 500m¬ of pineapple juice cost €1.40. How much for
(i) 1 litre?
(e) €56.47
(f) €112.50
(g) €275.25
(h) €560.34
(ii) 1 12 litres?
(e) 250m¬ of water is 80c. How much for
(i) 1 litre?
3. Solve the following.
(ii) 750m¬ ?
(a) How much for 1 tomato if 6 cost 96c?
(f) 1 12 kg of parsnips cost €1.20. How much for 1kg?
(b) 10 muffins cost €20. How much for 15 muffins?
(g) 2.5kg of turnips cost €2.50. How much for
(c) 6 eggs cost €2.28. How much for 12 eggs?
(i) 1kg?
(d) 500g of cornflakes cost €3.84. How much for 1kg of cornflakes?
(ii) 1 12 kg?
(e) 250m¬ of apple juice costs €0.85. How much for 750m¬ of the same apple juice?
(iii) 3000g?
(h) 0.75 metres of material costs €6.60. How much for
4. Which is better value for money?
(i) 1 metre?
(a) 6 bananas for €2.28 or 9 for €3.15?
(ii) 1.5 metres?
(b) 10 pencils for €5.50 or 15 for €7.95?
(iii) 500cm?
(c) 250m¬ of milk for €0.86 or 500m¬ for €1.50?
(d) 400g of butter for €1.90 or 2kg for €9?
2. Which is better value and by how much?
(e) 1 12 kg of wheatflakes for €3 or 1kg for €1.90?
(a) 8 plums for €3.84 or 6 for €2.70?
(b) 0.8 litres of hairspray for €1.80 or 1.2 litres for €2.50?
1
4 kg
1
2
of castor sugar for 79c or 750g for €2.40?
© Folens Photocopiables
Date: ___________________
© Folens Photocopiables
Name: _______________________________________
146
(c)
(d) 1
metres of string for €1.80 or 1 metre for €1.50? How much would I save if I bought
4 metres of string?
(e) 2 hours in the gym for €16 or 40 minutes for €5?
Name: _______________________________________
Date: ___________________
147
Fractions: Getting a fraction of an amount of money; finding the whole sum of money when a
fraction is known
Decimals: Getting a decimal fraction of an amount of money; finding the whole sum of money
when a fraction is known
Number: Operations involving the addition, subtraction multiplication and division of amounts of
money
SESE History: Change and continuity with regards to Irish currencies; development of trade,
bartering and money use
SESE Geography: Currencies of different countries; value of euro in developed and developing
countries
Children should be able to compare items in terms of value for money, for example: which
is better value, 3 tins of beans for €1·83 or 6 tins for €2·99? There are many contexts where
children should be able to apply this process to in the home, e.g. comparing value on broadband
packages, on mobile phone tariffs and on holidays.
Notes
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
78