Module 4- Workbook with Answers - Cambricollege

Module 4

Decimals

PODS

The following pods will be needed for the four lessons in Module 4:

1. Money | MATHS-21-001

2. Ordering Decimals | MATHS-18-001

3. Adding and Subtracting Decimals | MATHS-18-002

4. Multiplying Decimals MATHS-18-003

5. Dividing Decimals | MATHS-18-004

6. Solving Proportion Problems with Ratio | MATHS-17-003

7. Proportional Reasoning | MATHS-39-001

8. Rounding | MATHS-20-003

9. Rounding to Significant Figures | MATHS-20-008

10. Estimating | MATHS-20-004

11. Limits of Accuracy | MATHS-20-006

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https://members.gcsepod.com/shared/podcasts/title/12379/76211











Lesson 1

Money Problems POD

1. Money | MATHS-21-001

Quiz

Watch the pod and answer the questions below.

Do not use a calculator.

1. How many pence are there in £5.03?

a) 53p

b) 530p

c) 503p

d) 5030p

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2. John does a calculation involving money on his calculator and gets the answer 2.4pounds. How should he write his answer?

a) 2.4

b) £2.4

c) £2.40

d) 24p

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3. I buy 3 cakes for 45p each and sell them for 65p each. How much profit have I made?

a) 60p

b) £1.95

c) £1.35

d) 85p

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4. I see a pair of shoes that used to cost £45.60, but they are in a sale and have a £13.75 reduction. How much will they cost?

a) £38.73

b) £29.68

c) £59.35

d) £31.85

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5. I buy 3 pencils at 85p each, 2 notepads at £1.25 each and 5 pens at 97p each. How much change will I get from £10?

a) £9.90

b) 10p

c) 35p

d) £1.10

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6. I have £150 in a bank account. I get 5% interest a year. How much will I have at the end of one year?

a) £7.50

b) £57.50

c) £157.50

d) £142.50

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7. A chocolate bar costs 75p plus VAT at 20%. What is the total cost of the chocolate bar?

a) 90p

b) £1

c) 15p

d) 60p

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8. I earn £28,000 in a year. The first £15,000 is tax free and I pay 30% tax on the remainder. How much tax will I pay?

a) £8400

b) £3900

c) £9100

d) £16,900

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9. A pen costs 37p. How many pens can I buy for £2?

a) 3

b) 4

c) 5

d) 6

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10. A bag of 7 apples costs £2.30. I buy 3 bags of apples and 2 bags of bananas and it costs me £10.70. How much was a bag of bananas?

a) £4.20

b) £1.90

c) £1.09

d) £1.10

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Practise

Practise money problems.


1. To hire a car for 14 days it costs £310.10. How much does it cost per day?

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2. A cup of tea costs £1.65 and a cup of coffee costs £2.10. Find the cost of 2 cups of tea and 3 cups of coffee.

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3. Share £45 in the ratio 4 : 5

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4. A stamp costs 67p. Estimate the cost of 47 stamps. Will your answer be an under or overestimate?

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5. Mr Fisher and his two children want to go to an amusement park. The entrance tickets cost as follows:

Adult ticket = £40, Child ticket = £28, Family ticket (2 adults and 2 children) = £110

The amusement park currently has a special deal of 10% off the family ticket only.

Should Mr Fisher buy a family ticket? You must show your working out. ……………………………………………………………………………………………………………………………………………………………….. ………………………………………………………………………………………………………………………………………………………………..

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Practise

Practise money problems.

You may use a calculator.

1. Joanne has a rectangular shaped living room, measuring 5.1m by 2.4m. She wants tocover the floor in carpet that costs £8.95 per square metre. The area of all purchasesof carpet are rounded up to the next whole square meter. How much will it cost herto carpet the room?

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2. A bank pays 2% per year interest on money invested. Sammy invests £580 for oneyear. How much will he have in the account at the end of the year?

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3. Kian buys 2kg of peaches and 5kg of apples and it costs him £19.15.

A 1kg bag of peaches costs £3.45. How much is a kilogram of apples?

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4. Leah needs to buy 34 cupcakes for a party. Each cupcake costs £1.25. Leah has £40 tospend on the cupcakes. Does she have enough money?

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5. Jamil earns £28000 in a year. The first £11000 is tax free, and he pays 32% tax on therest. Find out how much he will receive after tax per month.

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6

Lesson 2

Four operations with decimals

PODS

2. Ordering Decimals | MATHS-18-0013. Adding and Subtracting Decimals | MATHS-18-0024. Multiplying Decimals MATHS-18-0035. Dividing Decimals | MATHS-18-004

Quiz

Watch the pods and answer the questions below.


1. Which is the smallest out of: 2.3, 2.35, 2.18, 2.301?

a) 2.3

b) 2.35

c) 2.18

d) 2.301

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2. Add together 4.75 and 1.1

a) 4.76

b) 5.76

c) 15.75

d) 5.85

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3. Work out 4.75 – 1.2

a) 3.73

b) 3.63

c) 3.55

d) 3. 68

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4. Work out 4 x 0.3.

a) 12

b) 1.2

c) 0.12

d) 0.012

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5. Work out 8.75 ÷ 5

a) 175

b) 1.85

c) 1.75

d) 0.175

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6. Work out 7.1 – 3.52

a) 3.58

b) 3.62

c) 3.60

d) 3.68

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7. Work out 2.7 x 1.5

a) 405

b) 40.5

c) 4.05

d) 0.405

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8. Which is the biggest? 0.805, 0.8, 0.85, 0.855

a) 0.805

b) 0.8

c) 0.85

d) 0.855

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9. How much change would you get from £10 if you spent £3.68?

a) £7.42

b) £6.42

c) £6.32

d) £7.32

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10. Work out 8 + 1.2 + 4.75

a) 139.5

b) 6.75

c) 6.03

d) 13.95

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Practise

Practise adding, subtracting, multiplying and dividing with decimals.


1. Put the following decimals in order from smallest to largest.

5.3, 5.03, 5.33, 5.303

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2. Work out 3.7 x 0.29

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3. Four blocks of wood are placed together in a row. Find the total length of the flour blocks.

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4. Alex gets £8.14 an hour. On Monday he works 8 hours. Find out how much he earns

altogether on Monday.

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5. Sean buys 2 pens at 78p each, 3 pencils at 35p each and a notebook for £3.80. How much

change will he get from £10?

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Practise

Practise adding, subtracting, multiplying and dividing with decimals.


1. A floor is the shape of a rectangle, measuring 2.1m and 3.7m. Find the area of the floor.

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2. Tommy has a plank of wood measuring 2.1m long. He needs to cut pieces that are0.32m long. How many pieces can he get from the plank of wood?

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3. Calculate 0.213.

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4. A rectangle has an area of 9.348cm2. The length of the rectangle is 3.8cm. Find thewidth of the rectangle.

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5. Tina has a rectangular garden that measures 3.5m by 4.7m. She wants to fence all theway round the garden. Fence panels cost £5.99 per metre, and you must buy a wholenumber of metres.

How much will it cost to fence the garden?

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Lesson 3

Converting Currencies and Best Buy

POD

6. Solving Proportion Problems with Ratio | MATHS-17-0037. Proportional Reasoning | MATHS-39-001

Quiz

Watch the pod and answer the questions.

You may use a calculator

1. The conversion rate of pounds to euros is £1 = 1.13 euros. How many pounds would Iget for 55 euros?

a) £62.15

b) £621.50

c) 0.021

d) £48.67

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2. The currency conversion is £1 = 28.9 Czech Krona. I want to convert £180 into Krona.How many Krona would I get?

a) 2890 krona

b) 28.90 krona

c) 622.8 krona

d) 5202 krona

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3. A box of cereal costs £4.35 for 2.5 kg. How much does it cost for 1kg?

a) £1.74

b) £10.88

c) 57p

d) £1.75

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4. A pack of sugar costs £1.25 for 500g. How much for 1kg?

a) 25p

b) £2.50

c) £25

d) £4

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5. A carton of orange juice costs £4.65 for 1 litre. How much for 250ml? Give your answer to the nearest penny.

a) £1.16

b) £1.17

c) 11.6p

d) £2.15

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6. 1 Australian dollar is equivalent to 0.75 US dollars. I buy a watch costing 154 US dollars. How much would it cost in Australian dollars? Give your answer correct to 2 d.p.

a) $115.5

b) $11.55

c) $205.33

d) $20.53

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7. The conversion rate is £1 = $1.35. A pair of sunglasses costs $125 in the US and £110 in the UK. In which country is it better value?

a) UK

b) US

c) Both the same

d) You don’t have enough information to tell

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8. A carton of juice costs £2.45 for 540ml. How much for a litre? Give your answer to the nearest penny.

a) £0.453

b) £4.53

c) £45.37

d) £4.54

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9. A car travels 220 miles in 3 hours 20 minutes. What is its average speed?

a) 68.75 mph

b) 62.9 mph

c) 66 mph

d) 87 mph

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10. A bag of 1.2kg of apples costs £3.66. How much do they cost per kilogram?

a) £3.05

b) 30.5p

c) £4.39

d) 43.9p

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Practise

Practise money and decimals.


1. Boxes of cereal come in 3 sizes:

Which is the best value for money?

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2. Jake wants to convert pounds to dollars. He knows the conversion rate is 1 US dollar = 88p. He needs to have $250. He works out how many pounds he will need to change by doing the following sum:

250 ÷ 0.88

Is he correct? Explain your answer.

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3. Toilet rolls come in packets of 2 or 9.

A pack of 2 costs 64p.

A pack of 9 costs £2.79.

Which is the best value for money? Show your working.

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4. Tia wants to work out how much 100ml of toothpaste costs to allow her to compare it to another. It costs £3.65 for a tube of 250ml. She thinks she should do the following sum:

250 ÷ 3.65

Is she correct? Give a reason for your answer.

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5. In a shop, cans of cola cost 35p. There are two offers: Offer 1: Buy two get one free! Offer 2: Buy six for £1.30 Which deal is better? Show your working.

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5

Practise

Practise money and decimals.


1. Hannah wants to buy a pair of shoes, and she lives in the UK. They cost £55 in the UK and$65 in the US. The currency conversion is £1 = $1.35.

a) In which country are the shoes cheapest? Show your working.

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b) What else might she have to take into account?

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2. In a supermarket, potatoes cost £1.35 for 1.3kg

In the local greengrocers, potatoes cost 85p for 850g

Which is the best deal? Show your working.

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3. An mp3 player is sold online and in a shop.

The shop is offering 20% off the usual price of £140.

Online, the mp3 player is £95 plus VAT at 20%.

Which is cheaper? Show your working.

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4. A car costs £23,500 in the UK and $26,750 in the US.

The currency rate is £1 = $1.35.

It will cost £1267.23 to import the car from the US to the UK.

Harry lives in the UK.

Should he buy it from the US or the UK? Show your working.

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5. Toothpaste comes in three different size tubes.

20ml = 37p

100ml = £1.55

250ml = £4.25

Which is the best value? You must show your working out.

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Lesson 4

Accuracy

PODS

8. Rounding | MATHS-20-0039. Rounding to Significant Figures | MATHS-20-00810. Estimating | MATHS-20-00411. Limits of Accuracy | MATHS-20-006

Quiz

Watch the pod and answer the questions.

You may use a calculator

1. Round 34,687 to the nearest hundred.

a) 34,796

b) 34,700

c) 34,600

d) 23,798

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2. Round 23.78 to the nearest tenth.

a) 24.0

b) 20

c) 23.8

d) 23.7

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3. Round 0.070568 to 3 significant figures.

a) 0.07051

b) 0.071

c) 0.07

d) 0.0706

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4. Round 70,456 to 3 significant figures.

a) 70,500

b) 70,460

c) 705

d) 7046

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5. If you were estimating the answer to 456 x 3.8 by rounding the numbers in the calculation to 1 significant figure, which calculation should you use?

a) 400 x 4

b) 460 x 3

c) 500 x 4

d) 460 x 4

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6. Estimate the answer to 3.92 ÷ 7.82

a) 1.945

b) 2

c) 1

d) 0.25

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7. Estimate the answer to #$.&×#.)&*.$+

a) 150

b) 37.5

c) 120

d) 30

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8. A plank of wood is measured as 50cm to the nearest 10cm. What is the shortest possible length of the plank of wood?

a) 40cm

b) 47.5cm

c) 49.5cm

d) 45cm

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9. A piece of string is measured as 200cm to the nearest 10cm. Which of the following isthe error interval for the length of the string, xcm?

a) 195cm ≤x < 205cm

b) 190cm ≤ x < 210cm

c) 199.5cm ≤x < 200.5cm

d) 195cm ≤x ≤205cm

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10. What is 2/3 written as a decimal and rounded to 2 decimal places?

a) 2.33

b) 0.66

c) 0.67

d) 2.23

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Practise

Practise accuracy.


1. A pencil measures 12.462cm in length. Round this to:

a) The nearest integer ………………………………………………………………………………………………………..

b) 1 decimal place ………………………………………………………………………………………………………..

c) 2 decimal places ………………………………………………………………………………………………………..

2. Round 109.962 to 1 decimal place.

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3. Round 3.5555 to:

a) 1 decimal place ………………………………………………………………………………………………………..

b) 2 decimal places ………………………………………………………………………………………………………..

4. Estimate the answer to 11.92 ÷ (17.26 x 0.529)

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5. The mass of a dog is measured as 12kg to the nearest kg. What is the error interval for themass of the dog?

………………………………kg ≤ Mass < ………………………………kg

4

Practise

Practise accuracy.


1. A number is rounded to the nearest hundred to give 700. What is the smallest value thatthe number could have been before it was rounded?

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2. Estimate the area of the rectangle:

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3. Round 20.5097 to:

a) the nearest integer ……………………………………………………………………………………………….

b) 1 decimal place ……………………………………………………………………………………………….

c) 2 significant figures ……………………………………………………………………………………………….

d) 3 decimal places ……………………………………………………………………………………………….

4. √./.&×$./#*.$/&

a) Estimate the value of the above expression.

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b) Use your calculator to find the exact answer of the above expression. Write outyour whole calculator display in decimal form.

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5. A flea has a mass of 0.005grams measured to 1 significant figure. What is the error intervalfor the mass of the flea?

………………………………g ≤ Mass < ………………………………g

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Apply

Apply what you have revised about money and decimals.


Remember

When working with money, convert all amounts to either pence or pounds before starting any calculations.

When comparing decimals, use zeros to make all numbers have the same number of digits after the decimal point and then compare number size easily.

Line up the decimal points when you are adding or subtracting decimal values.

Estimate an answer to any multiplication and division questions using rounded values and use this to check your answer. Is it what you expected? If not, go back and check your calculations.

Include units in your answer, e.g. £, and check whether the question asks for specific units.

Where necessary, finish questions with a concluding sentence stating what your calculations have shown, especially when deciding on best value or converting currencies.

1. You are given that 23.75 x 1.81 = 42.9875.

Use this information to find the following.

a) 0.2375 x 1.81

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b) 2.375 x 18.1

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c) 42.9875 ÷ 23.75

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d) 4298.75 ÷ 1.81

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e) 429.875 ÷ 2375

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2. Evaluate 7.82

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3. Danielle takes part in a race and her time, t, is given as 54.3 seconds, rounded to 1decimal place.

Write down the error interval for her time.

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4. Jenny does the following sum.

0.78 x 0.56 = 4.368

Explain how you know that Jenny doesn’t have the right answer.

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5. Write down a number between 5.46 and 5.47.

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6. Calculate

45.1 – 3.5 x 7

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7. Janie has £3.65, Tom as £4.72 and Jimmy has £12.60.

They decide to share it out equally amongst themselves. How much do they geteach?

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8. Put the following in order from smallest to largest.

2.305, 2.3, 2.301, 2.37, 2.1, 2.2951

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9. Sian says that when a number is cubed, the result is always at least as big as thenumber which was cubed. Give an example to show that Sian is wrong.

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10. A pint of milk costs 89p. There are 1.8 pints in a litre. Work out the cost of 1 litre of milk.Give your answer to the nearest penny.

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Apply

Apply what you have revised about money and decimals.


Remember

When working with money, convert all amounts to either pence or pounds before starting any calculations.

When comparing decimals, use zeros to make all numbers have the same number of digits after the decimal point and then compare number size easily.

Line up the decimal points when you are adding or subtracting decimal values.

Estimate an answer to any multiplication and division questions using rounded values and use this to check your answer. Is it what you expected? If not, go back and check your calculations.

Include units in your answer, e.g. £, and check whether the question asks for specific units.

Finish all questions with a concluding sentence stating what your calculations have shown, especially when deciding on best value or converting currencies.

1. √$..0.&.+..#1

a) Estimate the solution to this expression.

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b) Work out the exact answer to the above expression using your calculator:

i) Write down the full display of your calculator in decimal form.

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ii) Round your answer to 1 decimal place.

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2. A supermarket has an offer on packets of sweets.

A bag of 6 packets costs £2.30 and 2 bags of 6 packets cost £4.20. A bag of 10 packets costs £3.60 and 2 bags of 10 packets cost £7.10.

Joanna needs to buy 60. What is the cheapest way?

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3. Alexis stays at a hotel for 6 nights.

While she is there she has two breakfasts and three dinners.

A breakfast costs £6.75 and a dinner costs £37.50.

When she leaves, the total bill is £567.

Work out how much the hotel cost per night.

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4. James pays 17.1p per unit of electricity.

In May he uses 254.3 units.

He then swaps to a company which charge 15.2p per unit and in the month of June he uses 275 units.

In which month did he pay more and by how much?

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5. Dan decides to work out how much money he will receive this month.

He has worked 110 hours at £15.23 per hour.

He has worked 46 hours at £16.47 per hour.

He also gets a bonus of 15.2p per hour worked.

He pays £268.96 tax.

He pays £372.24 National Insurance.

How much does he receive? Give your answer to the nearest penny.

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6. A bank pays 4.2% interest.

Luna invests $4750.

How much does she have at the end of the year?

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7. Which of the following decimals is closest to #) ?

0.3, 0.75, 0.38, 0.401, 0.39, 0.23, 0.2, 0.3

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8. I want to invest £5000 for two years.

Bank A offers 2.6% per year.

Bank B offers 3.1% for the first year and then 0.5% for the second year.

Both banks offer compound interest.

Would I have the same amount of money in both at the end of the two years? Show all ofyour working.

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9. A shirt costs £37.50.

The shop which sells the shirt has a sale of 40%.

It then further reduces the price by 60%.

Jimmy says that the shirt must now be free as 40 + 60 = 100%.

Show that Jimmy is wrong.

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10. Grainne measures a pencil. She writes down the length as follows, but then she spillsink on her page:

What is the error interval for the length of the pencil?

…………………………cm ≤ Length < …………………………cm

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Answer Keys

Please refer to workbook for question content

Module 4

Money and Decimals

Lesson 1

Money Problems

Quiz

1. c) 503p

2. c) £2.40

3. a) 60p

4. d) £31.85

5. b) 10p

6. c) £157.50

7. a) 90p

8. b) £3900

9. c) 5

10. b) £1.90

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Practise (Non-Calculator)

1. 310.10 / 14 = £22.15

2. Add together 1.65 + 1.65 + 2.10 + 2.10 + 2.10 = £9.60

3. 4 + 5 = 945 ÷ 9 = 54 × 5 : 5 × 5 = £20 : £25

4. The approximate cost is then 70p and the approximate number of stamps bought is50.50 × 70 = 3500p = £35 and this is an overestimate as we rounded up with bothnumbers.

5. 1 adult and 2 child tickets = 40 + 28 + 28 = £9610% of 110 = 11, new price of a family ticket = 110 – 11 = £99No, it is cheaper to buy individual tickets

2

Practise (Calculator)

1. Area of the room = 5.1 × 2.4 = 12.24 m2

Would need to buy 13m2 so Cost = 13 × 8.95 = £116.35

2. 2% of 580 = 580 / 100 × 2 = 11.6Interest is added on: 580 + 11.6 = £591.60

3. 19.15 – 2 × 3.45 = 12.2512.25 / 5 = 2.451 kg of apples = £2.45

4. 34 × 1.25 = £42.50No, Leah does not have enough money - she needs £2.50 more

5. 28000 – 11000 = 1700032% of 17000 = 17000 / 100 × 32 = 5440 taxHis net pay per year is 2800028000 - 5440 = 22560

Per month: 22560 / 12 = 1880

Jamil receives £1880 per month.

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Lesson 2

Four Operations with Decimals

Quiz

1. c) 2.18

2. d) 5.85

3. c) 3.55

4. b) 1.2

5. c) 1.75

6. a) 3.58

7. c) 4.05

8. d) 0.855

9. c) £6.32

10. d) 13.95

4


1. Easiest if you have the same number of decimal places (digits to the right of the decimal point): 5.300, 5.030, 5.330, 5.303 Now we can compare the numbers to the right of the decimal point as they all start with a 5 5.030, 5.300, 5.303, 5.330 Order of original numbers is: 5.03, 5.3, 5.303, and 5.33

2. First work out 37 × 29 37 x 29 333 740 1073

Now look at the question. There are 3 numbers to the right of decimal points in the question, so we need 3 decimal places in the answer 1.073

3.

Add together 2 . 1 1 . 7 2 2 . 7 9 2_____ 8 . 6 1 cm

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4. Multiply 8.14 × 8 = £65.12

5. 0.78 × 2 = 1.56 0.35 × 3 = 1.05 3.80 Total cost = £6.41 10 – 6.41 = £3.59

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1. 2.1 × 3.7 = 7.77m2

2. 2.1 ÷ 0.32 = 6.5625So he can get 6 full pieces.

3. This means 0.21 × 0.21 × 0.21 = 0.009261

4. 9.348 ÷ 3.8 = 2.46cm

5. Perimeter = 3.5 + 4.7 + 3.5 + 4.7 = 16.4mNeed to buy 17m of fencing17 × 5.99 = £101.83

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Lesson 3

Converting Currencies and Best Buy

Quiz

1. d) £48.67

2. d) 5202 krona

3. a) £1.74

4. b) £2.50

5. a) £1.16

6. c) $205.33

7. b) US

8. d) £4.54

9. c) 66 mph

10. a) £3.05

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1. 2kg box is 2.40 ÷ 2 = £1.20 per kg3kg = 3.54 ÷ 3 = £1.18 per kg500g = 0.55 × 2 = £1.10 per kgThe box of 500g is the best value for money as it is cheapest per kg

2. No, as this would give a bigger answer and he should expect a smaller answer. Heshould do 250 × 0.88 = £220

3. 64 ÷ 2 = 32p each2.79 ÷ 9 = 31pThe pack of 9 is better value as it is cheaper per roll

4. No, this would give her the amount of toothpaste for £1, not the price for 100 ml. Sheshould do 3.65 ÷ 250 × 100

5. Buy two get one free means that 3 cans cost 70pBuy six for £1.30 would mean that 3 cans would cost 65pSo the buy six offer is better

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1. a) £55 × 1.35 = $74.25.So they are cheaper in the USb) She would have to pay to get them imported / delivered which might be moreexpensive

2. 1.35 ÷ 1.3 = £1.038 for 1 kg0.85 ÷ 0.850 = £1 for 1 kgThe greengrocer is better value as it is £1 for 1kg of potatoes

3. Shop: 140 × 0.8 = £112Online: 95 × 1.2 = £114Shop is the best deal

4. 26750 ÷1.35 = £19814.81Add on the import cost = 19814 + 1267.23 = £21082.04Cheaper to buy from the US

5. Compare the price of each for 100ml:20ml tube = 0.37 × 5 = £1.85100ml tube = £1.55250 ml = 4.25 ÷ 2.5 = £1.70The 100ml tube is the best value

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Lesson 4

Accuracy

Quiz

1. b) 34,700

2. c) 23.8

3. d) 0.0706

4. a) 70,500

5. c) 500 x 4

6. b) 2

7. c) 120

8. d) 45cm

9. a) 195cm≤x<205cm

10. c) 0.67

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1. a) 2cm

b) 12.5cm

c) 10cm

2. 110.0

3. a) 3.6

b) 3.56

4. Round all values to 1 significant figure: 10²÷ (20x0.5) = 100÷ 10 = 10

5. 11.5kg ≤ Mass < 12.5kg

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1. 160

2. Round all values to 1 significant figure when estimating:

10 x 8 = 80cm2

3. a) 21b) 20.5c) 21d) 20.510

4. a) Round all values to 1 significant figure:

≈√20 × 50.5

=√1000.5

=100.5

= 20

b) 18.84045979 (at least 5 decimal places shown)

5. 0.0045g ≤ Mass < 0.0055g

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Apply (Non-Calculator)

1. a) 0.429875b) 42.9875c) 1.81d) 2375e) 0.181

2. 7.8 × 7.8 = 60.84

3. 54.25 seconds ≤ t < 54.35 seconds

4. If you multiply two numbers which are both less than 1, the result will be less than 1.4.368 is greater than 0.78 and 0.56, so it cannot be right.

5. Adding a 0 helps5.460 and 5.470For example, 5.465

6. BIDMAS: 3.5 × 7 first = 24.545.1 – 24.5 = 20.6

7. 3.65 + 4.72 + 12.60 = £20.9720.97 ÷ 3 = £6.99

8. Adding zeros will help:2.3050, 2.3000, 2.3010, 2.3700, 2.1000, and 2.2951 – they all start with a 2 so comparethe numbers after the decimal point:2.1, 2.2951, 2.3, 2.301, 2.305, 2.37

9. For example, 0.23 = 0.2 × 0.2 × 0.2 = 0.008 which is less than 0.2Any number less than 1 will cube to give a number that is less that itself.

10. 1.8 × 89 = 160.2 = £1.60

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Apply (Calculator)

1. a)

√4.1 + 19.81.20

≈√4 + 20

1

≈√251

=51= 5

b. i) 3.394974045

ii) 3.4

2. For 1 bag of 6 packets 2.30 ÷ 6 = 38.3p per packetFor 2 bags of 6 packets 4.20 ÷ 12 = 35p per packetFor 1 bag of 10 packets 3.60 ÷ 10 = 36p per packetFor 2 bags of 10 packets 7.10 ÷ 20 = 35.5pTherefore, buying the 2 packs of 6 is the best value; she should buy 5 lots of this deal.

3. 6.75 × 2 + 37.50 × 3 = £126567 – 126 = 441441 / 6 = £73.50 a night

4. May: 17.1 × 254.3 = 4348.53 pence, which is £43.49June: 15.2 × 275 = 4180 pence £41.80He pays less in June by £1.69

5. 110 × 15.23 + 46 × 16.47 = 2432.9215.2 × 156 = 2371.2 = £23.71Total pay = 2456.632456.63 – 268.96 – 372.24 = £1815.43

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6. 4750 ÷ 100 × 4.2 = 199.5 Total = 4750 + 199.5 = $4949.50

7. 01 is = 0.4, so 0.401 is closest

8. Bank A: 100% + 2.6% = 102.6% = 1.026 5000 × 1.026 × 1.026 = £5263.38 You could also do: 5000 ÷ 100 × 2.6 = 130 5000 + 130 = £5130 after 1 year 5130 ÷ 100 × 2.6 = 133.38 5130 + 133.38 = £5263.38 Bank B 5000 ÷ 100 × 3.1 = 155 5000+155 = £5155 after 1 year 5155 ÷ 100 × 0.5 = 25.775 5155+ 25.775 = £5180.775 Bank A offers more interest.

9. 37.50 ÷ 100 × 40 = 15 37.50 – 15 = £22.50 22.5 ÷ 100 × 60 = 13.50 22.50 – 13.50 = £9

10. 8.6cm ≤ Length < 8.7cm

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Module 4- Workbook with Answers - Cambricollege

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Transcript of Module 4- Workbook with Answers - Cambricollege