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MODULE 4 WORKBOOKMoney and Decimals
Commissioned by GCSEPod.This resource is strictly for the use of subscribing schools for as long as they remain subscribers This resource is strictly for the use of subscribing schools for as long as they remain subscribers of GCSEPod. It may not be copied, sold, or transferred to a third party or used by the school after subscription ceases. Until such time it may be freely used within the subscribing school. All opinions and contributions are those of the authors. The contents of this resource are not connected with, or endorsed by, any other company, organisation or institution. GCSEPod will endeavour to trace and contact copyright owners. If there are any inadvertent omissions or errors in the acknowledgements or usage, this is unintended and GCSEPod will remedy these on written notification.
7 May 2019
Contents
Lesson 1 p 3
Lesson 2 p 8
Lesson 3 p 13
Apply (Non-calculator) p 20
Apply (Calculator) p 23
2
Module 4
Decimals PODS Before continuing, make sure you have watched and have access to the following Pods. To find these, simply log in to GCSEPod and enter the codes given into the search bar (or click on the titles below).
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 involving ratio | MATHS-17-003
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
3
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
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
4. I see a pair of shoes that used to cost £45.60, but they are in a sale and have a £13.75reduction. How much will they cost?
a) £38.73
b) £29.68
c) £59.35
d) £31.85
………………………………………………………………………………………………………………………………………………………………..
5. I buy 3 pencils at 85p each, 2 notepads at £1.25 each and 5 pens at 97p each. Howmuch change will I get from £10?
a) £9.90
b) 10p
c) 35p
d) £1.10
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
6. I have £150 in a bank account. I get 5% interest a year. How much will I have at the endof one year?
a) £7.50
b) £57.50
c) £157.50
d) £142.50
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
4
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
8. I earn £28,000 in a year. The first £15,000 is tax free and I pay 30% tax on theremainder. How much tax will I pay?
a) £8400
b) £3900
c) £9100
d) £16,900
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
9. A pen costs 37p. How many pens can I buy for £2?
a) 3
b) 4
c) 5
d) 6
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
10. A bag of 7 apples costs £2.30. I buy 3 bags of apples and 2 bags of bananas and itcosts me £10.70. How much was a bag of bananas?
a) £4.20
b) £1.90
c) £1.09
d) £1.10
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
5
Practise
Practise money problems.
Do not use a calculator.
1. To hire a car for 14 days it costs £310.10. How much does it cost per day?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
2. A cup of tea costs £1.65 and a cup of coffee costs £2.10. Find the cost of 2 cups of teaand 3 cups of coffee.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
3. Share £45 in the ratio 4 : 5
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
4. A stamp costs 67p. Estimate the cost of 47 stamps. Will your answer be an under oroverestimate?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
5. Mr Fisher and his two children want to go to an amusement park. The entrance ticketscost 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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6
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
7
Lesson 2
Four operations with decimals
PODS
3. Adding and subtracting decimals | MATHS-18-0024. Multiplying decimals | MATHS-18-003
Quiz
Watch the pods and answer the questions below.
Do not use a calculator.
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
………………………………………………………………………………………………………………………………………………………………..
2. Add together 4.75 and 1.1
a) 4.76
b) 5.76
c) 15.75
d) 5.85
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
3. Work out 4.75 – 1.2
a) 3.73
b) 3.63
c) 3.55
d) 3. 68
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
8
4. Work out 4 x 0.3.
a) 12
b) 1.2
c) 0.12
d) 0.012
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
5. Work out 8.75 ÷ 5
a) 175
b) 1.85
c) 1.75
d) 0.175
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
6. Work out 7.1 – 3.52
a) 3.58
b) 3.62
c) 3.60
d) 3.68
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
7. Work out 2.7 x 1.5
a) 405
b) 40.5
c) 4.05
d) 0.405
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
9
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
10. Work out 8 + 1.2 + 4.75
a) 139.5
b) 6.75
c) 6.03
d) 13.95
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
10
Practise
Practise adding, subtracting, multiplying and dividing with decimals.
Do not use a calculator.
1. Put the following decimals in order from smallest to largest.
5.3, 5.03, 5.33, 5.303
………………………………………………………………………………………………………………………………………………………………..
2. Work out 3.7 x 0.29
………………………………………………………………………………………………………………………………………………………………..
3. Four blocks of wood are placed together in a row. Find the total length of the flour blocks.
………………………………………………………………………………………………………………………………………………………………..
4. Alex gets £8.14 an hour. On Monday he works 8 hours. Find out how much he earns
altogether on Monday.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
11
Practise
Practise adding, subtracting, multiplying and dividing with decimals.
You may use a calculator.
1. A floor is the shape of a rectangle, measuring 2.1m and 3.7m. Find the area of the floor.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
3. Calculate 0.213.
………………………………………………………………………………………………………………………………………………………………..
4. A rectangle has an area of 9.348cm2. The length of the rectangle is 3.8cm. Find thewidth of the rectangle.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
12
Lesson 3
Converting Currencies and Best Buy
POD
6. Solving proportion problems involving ratio | MATHS-17-003
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
13
4. A pack of sugar costs £1.25 for 500g. How much for 1kg?
a) 25p
b) £2.50
c) £25
d) £4
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
5. A carton of orange juice costs £4.65 for 1 litre. How much for 250ml? Give your answerto the nearest penny.
a) £1.16
b) £1.17
c) 11.6p
d) £2.15
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
7. The conversion rate is £1 = $1.35. A pair of sunglasses costs $125 in the US and £110 inthe UK. In which country is it better value?
a) UK
b) US
c) Both the same
d) You don’t have enoughinformation to tell
………………………………………………………………………………………………………………………………………………………………..
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14
8. A carton of juice costs £2.45 for 540ml. How much for a litre? Give your answer to thenearest penny.
a) £0.453
b) £4.53
c) £45.37
d) £4.54
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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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15
Practise
Practise money and decimals.
Do not use a calculator.
1. Boxes of cereal come in 3 sizes:
Which is the best value for money?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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 changeby doing the following sum:
250 ÷ 0.88
Is he correct? Explain your answer.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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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16
4. Tia wants to work out how much 100ml of toothpaste costs to allow her to compare itto another. It costs £3.65 for a tube of 250ml. She thinks she should do the followingsum:
250 ÷ 3.65
Is she correct? Show your working.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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 £1.30Which deal is better? Show your working.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
17
Practise
Practise money and decimals.
You may use a calculator.
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
b) What else might she have to take into account?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
18
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
19
Apply
Apply what you have revised about money and decimals.
Do not use a calculator.
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
b) 2.375 x 18.1
………………………………………………………………………………………………………………………………………………………………..
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20
c) 42.9875 ÷ 23.75
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
d) 4298.75 ÷ 1.81
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
e) 429.875 ÷ 2375
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
2. Evaluate 7.82
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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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21
5. Write down a number between 5.46 and 5.47.
………………………………………………………………………………………………………………………………………………………………..
6. Calculate
45.1 – 3.5 x 7
………………………………………………………………………………………………………………………………………………………………..
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
8. Put the following in order from smallest to largest.
2.305, 2.3, 2.301, 2.37, 2.1, 2.2951
………………………………………………………………………………………………………………………………………………………………..
9. Sian says that any number cubed always gives either the same or a bigger value. Givean example to show that Sian is wrong.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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.
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
22
Apply
Apply what you have revised about money and decimals.
You may use a calculator.
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. Work out the following using your calculator.
√4.1 + 19.81.2+
a) Write down the full display of your calculator.
………………………………………………………………………………………………………………………………………………………………..
b) Round your answer to 1 decimal place.
………………………………………………………………………………………………………………………………………………………………..
23
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 heuses 275 units.
In which month did he pay more and by how much?
………………………………………………………………………………………………………………………………………………………………..
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24
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?
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
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
………………………………………………………………………………………………………………………………………………………………..
………………………………………………………………………………………………………………………………………………………………..
25
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 offercompound interest.
Would I have the same amount of money in both at the end of the two years? Showall of your 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. A pencil is measured as 8.6cm to one decimal place. Write down the error interval of l,the length of the pen.
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