Mastering Mathematics 5B

WMPB15034B

Special Features

3 Topical-based practices 3 Revision papers and Semestral assessment

3 Challenging questions 3 Complete answers

Mastering Mathematics Workbook 5B

Mastering Mathematics is a comprehensive series of assessment workbooks which is written based on the latest Primary Mathematics Syllabus issued by the Ministry of Education of Singapore. Each of the workbooks provides sufficient practices on various types of questions. The approach adopted by the writers aims at reinforcing mastery of mathematical concepts, improving problem-solving skills and developing creative and critical thinking skills.

PELANGI

Topic-By-Topic

Latest

MOE Syllabus

Primary

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Published by:

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Pelangi Publishing Singapore Pte. Ltd.

In collaboration with:

Dickens Publishing Ltd. Suite G7-G8, Davina House, 137-149 Goswell Road, London, EC1V 7ET, United Kingdom.

E-mail: info@dickenspublishing.co.uk

( 201112597 C )

WMPB15034B

ISBN: 978-981-07-1233-4

,!7IJ8B0-hbcdde!

In collaboration with Dickens Publishing Ltd. (UK)

Lilian Yeo

Unit 7

Decimals......................................................... 1

Unit 8

Measurements ................................................ 8

General Revision 1......................................................... 14 Unit 9

Average ....................................................... 18

Unit 10

Percentage ................................................... 26

General Revision 2 ........................................................ 35 Unit 11

Angles ......................................................... 39

Unit 12

Properties of Triangles and Four-Sided Figures ......... 46

General Revision 3 ........................................................ 54 Unit 13

Geometrical Construction ................................... 60

Unit 14

Volume of Cube and Cuboid .............................. 66

General Revision 4 ........................................................ 76 Semestral Assessment ................................................... 82 Answers .................................................................. 97

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Mathematics Primary 5B Unit 7 Decimals

7

Decimals

A Convert each decimal to a fraction or mixed number. Give your answer in

its simplest form.

1. 0.5 =

2. 5.3 =

3. 420.8 =

4. 0.07 =

5. 8.26 =

6. 17.05 =

7. 109.85 =

8. 0.009 =

9. 0.204 =

10. 51.024 =

11. 35.312 =

12. 821.009 =

13. 52.294 =

14. 78.245 =

B Find the value of each of the following.

1. 0.9 × 10 =

2. 5.23 × 10 =

3. 163.708 × 10 =

4. 0.07 × 100 =

5. 43.2 × 100 =

6. 26.285 × 100 =

7. 0.81 × 1000 =

8. 74.05 × 1000 =

9. 672.49 × 1000 =

10. 0.364 × 1000 =

1

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Mathematics Primary 5B Unit 7 Decimals

C Find the missing numbers.

1. 4.3 ×

= 43

2. 0.813 ×

= 81.3

3. 509.2 ×

= 5092

4. 0.069 ×

= 6.9

5. 71.56 ×

= 7156

6. 573.9 ×

= 57 390

7. 0.0895 ×

= 89.5

8. 8631.5 ×

= 863 150

9. 3.0582 ×

= 30.582

10. 29.301 ×

= 29 301

D Fill in each blank with the correct answer.

1. 0.7 × 30 = 0.7 × 3 × 10

2. 25 × 200 = 25 × 2 × 100

=

× 10

=

=

=

× 100

3. 42.3 × 500 = 42.3 × 5 ×

=

=

×

4. 924.3 × 8000 = 924.3 ×

=

=

× ×

5. 0.0743 × 9000 = 0.0743 ×

=

=

× ×

2

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Mathematics Primary 5B Unit 7 Decimals

E Find the value of each of the following.

1. 0.3 ÷ 10 =

2. 54.7 ÷ 10 =

3. 508 ÷ 10 =

4. 1.2 ÷ 100 =

5. 62.7 ÷ 100 =

6. 3716 ÷ 100 =

7. 534 294 ÷ 1000 =

8. 6379 ÷ 1000 =

9. 72 ÷ 1000 =

10. 972 ÷ 100 =

F Find the missing numbers.

1.

÷ 10 = 7.3

2.

÷ 10 = 56.3

3.

÷ 10 = 945.6

4.

÷ 100 = 0.364

5.

÷ 100 = 328.4

6.

÷ 100 = 0.027

7.

÷ 1000 = 0.008

8.

÷ 1000 = 36

9.

÷ 1000 = 51.3

10.

÷ 100 = 62 500

G Fill in each blank with the correct answer.

1. 60 ÷ 30 = 60 ÷ 3 ÷ 10

2. 35.5 ÷ 500 = 35.5 ÷ 5 ÷ 100

=

÷ 10

=

=

=

÷ 100

3

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Mathematics Primary 5B Unit 7 Decimals

3. 960 ÷ 800 = 960 ÷

=

=

÷ ÷

4. 42 ÷ 7000 = 42 ÷

=

=

÷ ÷

5. 37 800 ÷ 2000 = 37 800 ÷

=

=

÷

÷

H Write your answers on the lines provided.

1. 2.3 kg + 34.05 kg =

g

2. $305.20 – $259.70 = $ 3. 57.3 cm × 300 = 4. 4907 g ÷ 700 =

m g

5. Add 713 g to 12.8 g =

g

6. Multiply 1 hour 10 minutes by 20.

Give your answer in hours and minutes.

7. Divide 165.06 l by 70.

8. Subtract 0.24 m from 34 m.

h

min l m

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Mathematics Primary 5B Unit 7 Decimals

I Solve the following word problems.

1. 9 similar books cost $121.05. How much does each book cost?

2. A piece of string measures 43.2 cm. What is the total length of a dozen of such strings?

3. Jane bought 6.3 kg of grapes and 9.6 kg of strawberries. If the grapes cost $22 per kg and the strawberries cost $14 per kg, how much in total did Jane pay for the fruits?

5

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Mathematics Primary 5B Unit 7 Decimals

4. Lisa mixed 2.3 l of water with 4 similar bottles of orange syrup. The volume of the total mixture is 3700 ml. What was the volume of orange syrup in each bottle at first?

5. Ben spends $22.35 on food every day. How much does he spend on food in a month? Assume there are 30 days in 1 month.

6. Alan had a roll of rope measuring 10 m. He cut out 5 equal pieces of rope each measuring 1.55 m from the original rope. What is the length of the remaining rope?

6

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Mathematics Primary 5B Unit 7 Decimals

7. A shopkeeper packed 19.25 kg of tapioca flour into 7 packets. The shopkeeper sold the tapioca flour at $5.20 per kg, find the price of each packet of tapioca flour.

8. Susan buys 6 dictionaries at $24.85 each and 8 textbooks at $14.60 each. If she pays $300 to the cashier, how much does she receive in change?

9. The exchange rate for 1 United States dollar is 1.24 Singapore dollar. If 500 United States dollars are to be exchanged for Singapore dollar, how much Singapore dollar will you get in return?

7

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Mathematics Primary 5B Unit 8 Measurements

8

Measurements

A Convert: 1. 15.4 m = 15.4 ×

=

2. 0.247 m = 0.247 ×

cm

3. 26.72 km = 26.72 ×

=

=

=

=

g

8. 0.089 l = 0.089 ×

=

ml

10. 76.1 cm = 76.1 ÷

m

11. 95 462 m = 95 462 ÷

=

ml

=

m

6. 678.28 kg = 678.28 ×

9. 4306 cm = 4306 ÷

=

g

7. 31.47 l = 31.47 ×

cm

4. 0.632 km = 0.632 ×

m

5. 5.792 kg = 5.792 ×

=

=

m

12. 21 m = 21 ÷

km

=

km

8

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Mathematics Primary 5B Unit 8 Measurements

13. 3026 g = 3026 ÷

=

kg

15. 94 160 ml = 94 160 ÷

14. 78 g = 78 ÷

=

=

kg

16. 8235 ml = 8235 ÷

l

=

l

B Convert: 1. 5.29 m = ? m ? cm

2. 247.01 m = ? m ? cm

0.29 m = 0.29 × 100 0.01 m

= 0.01 ×

=

=

cm

5.29 m =

m

cm 247.01 m =

3. 13.04 km = ? km ? m 0.04 km = 0.04 ×

=

13.04 km =

0.245 kg = 0.245 × =

26.245 kg =

cm

= 0.42 ×

m km

m

4. 603.42 km = ? km ? m 0.42 km

5. 26.245 kg = ? kg ? g

cm

=

m

m 603.42 km =

km

m

6. 9.003 kg = ? kg ? g 0.003 kg = 0.003 ×

g kg

=

g 9.003 kg =

g kg

g

9

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Mathematics Primary 5B Unit 8 Measurements

7. 82.14 l = ? l ? ml 0.14 l = 0.14 ×

=

8. 10.076 l = ? l ? ml 0.076 l = 0.076 ×

ml

82.14 l =

=

ml

ml 10.076 l =

l

ml

l

C Express, as a decimal: 1. 9 m 12 cm = ? m 12 cm =

2. 69 m 4 cm = ? m

12 = 100

m 4 cm =

9 m 12 cm = 9 m +

=

792

792 m =

=

=

m

m 69 m 4 cm = 69 m + m

3. 13 km 792 m = ? km

4

=

m m

4. 834 km 49 m = ? km km 49 m =

49

=

km

13 km 792 m 834 km 49 m = 13 km + =

km = 834 km +

km =

km

km

10

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Mathematics Primary 5B Unit 8 Measurements

5. 47 kg 9 g = ? kg 9 g =

9

6. 724 kg 320 g = ? kg

=

320

kg 320 g =

=

kg

47 kg 9 g 724 kg 320 g = 47 kg + =

kg = 724 kg + kg =

7. 2 l 5 ml = ? l 5 ml =

5

kg

kg

8. 91 l 27 ml = ? l =

27

l 27 m l =

=

l

2 l 5 ml 91 l 27 m l = 2 l + =

l = 91 l + l =

l l

11

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Mathematics Primary 5B Unit 8 Measurements

D Solve the following word problems.

1. David cut 5 m of wire into 20 equal pieces. Find the length of each piece of wire in cm.

1 of the volume of water 3 in Tank A. What is the total volume of water in both tanks? Give your answer in millimetres.

2. Tank A contains 27.3 l of water while Tank B contains

3. Mary used 4.41 kg of flour to make 7 cakes. How much flour does Mary need to make 11 cakes? Give your answer in grams.

12

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Mathematics Primary 5B Unit 8 Measurements

4. Robert lives 570 m from his school. He walks to school and returns home along the same route 5 days a week. How many kilometres does Robert travel in a week?

5. Mrs Lim bought 4 cartons of cans of raspberry juice for a party. Each carton contains 12 cans of raspberry juice. She emptied all the cans of drinks into a large container. The total volume of raspberry juice is 12.48 l. What is the volume of raspberry juice in each can at first? Give your answer in ml.

6. A curtain tailor receives an order for making 48 similar curtains. Each curtain requires 330 cm of cloth. Each roll of cloth was 40 m long. (a) How many rolls of cloth were needed to make 48 similar curtains? (b) If the curtain tailor buys 4 rolls of cloth, how much cloth did the tailor have left? Give your answer in metres. (Assume there was no wastage.)

13

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A Choose the correct answer and write its number in the brackets provided.

1. 23 ÷ 1000 = (1) 0.023 (3) 2.3

(2) 0.23 (4) 23 000

( )

2. Convert 9.35 to a fraction in its simplest form.

3 7 (1) 9 (2) 9 20 20 3 (3) 9 5

(4) 9

7

10

( )

3. Which of the following is not equivalent to 43.6?

(1) 43 600 ÷ 1000 (2) 4.36 × 10 (3) 0.436 × 100 (4) 4360 ÷ 10

( )

4. Subtract 0.078 ml from 741.2 ml.

(1) 740.42 ml (3) 741.278 ml

(2) 741.122 ml (4) 741.98 ml

( )

5. Convert 34.9 l to millilitres.

(1) 0.349 ml (3) 3490 ml

(2) 3.49 ml (4) 34 900 ml

( )

6. Express 273.4 cm in metres.

(1) 2.734 m (3) 2734 m

(2) 27.34 m (4) 27 340 m

( )

7. Express 3 kg 47 g as a decimal in kilograms.

(1) 3.047 kg (2) 3.47 kg (3) 3047 kg (4) 3470 kg

( )

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Mathematics Primary 5B General Revision 1

8. Which of the following is equivalent to 410 m?

(1) 0.041 km (2) 0.41 km (3) 0.41 cm (4) 4100 cm

( )

B Write your answers on the lines provided.

1. Find the difference between $312.65 and $9013.20.

2. Convert 420 km 17 m to metres.

3. Express 25 kg 15 g as a decimal in kilograms.

4. Find the product of 36.47 and 6000.

5. Judy jogs 720 m every day. How many kilometres does she jog in a week?

Express your answer in its simplest form or as a mixed number.

6. Bryan saves $274.35. Timothy saves three times as much money as Bryan. How much money do they save in total?

7. A grocer stacks up 115 identical boxes of cornflakes. If the thickness of each box is 3.5 cm, find the height of the stack of boxes of cornflakes. Give your answer in metres.

8. Pamela used 38 m of ribbon to tie 50 identical present boxes. How many centimetres of ribbon did she use for each present box?

15

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