Go Get Maths Workbook P6 samplebook

Workbook Prathomsuksa 6 © Pelangi Publishing (Thailand) Co., Ltd. 2022 All rights reserved. No part of this publication may be reproduced, stored in any retrieval system or transmitted in any form or by any means without permission of Pelangi Publishing (Thailand) Co., Ltd. 2022

BJRC366031_GoGetMaths WB Prelimpage P6.indd 1

885-87220-0364-7 First Published 2022

29/1/2565 BE 13:40

Contents Chapter 1

Chapter 2

Chapter 3

Chapter 4

Chapter 5

Chapter 6

Revision 1

Content SG Maths WB P6 page ii.indd 2

Factors and multiples

1

Practices

Chapter 7

Triangles

115

1

Practices

115

Think

20

Think

131

Fractions

21

Polygons

132

Practices

21

Practices

132

Think

39

Think

144

Decimals

40

Circles

145

Practices

40

Practices

145

Think

54

Think

163

Ratios

55

Volume and capacity

164

Practices

55

Practices

164

Think

68

Think

178

Percentages

69

Solids

179

Practices

69

Practices

179

Think

88

Think

188

Patterns

89

Pie charts

189

Practices

89

Practices

189

Think

104

Think

197

105

Chapter 8

Chapter 9

Chapter 10

Chapter 11

Chapter 12

Revision 2

198

17/12/2021 3:27 PM

Chapter 1 Factors and multiples Practice 1

Factors

1. Determine if each number is a factor of the number in the brackets. .g .

4 (60)

a 5 (35)

60 ÷ 4 = 15

35 ÷ 5 = 7

So, 4 is a factor of 60.

So, 5 is a factor of 35.

b 8 (104)

c

104 ÷ 8 = 13

123 ÷ 11 = 11 R 2

So, 8 is a factor of 104.

So, 11 is not a factor of 123.

d 9 (73)

e

73 ÷ 9 = 8 R 1

300 ÷ 25 = 12

So, 9 is not a factor of 73.

So, 25 is a factor of 300.

11 (123)

25 (300)

2. List the factors of these numbers.

.g .

8

1, 2, 4, 8

a

15

1, 3, 5, 15

b

24

1, 2, 3, 4, 6, 8, 12, 24

c

35

1, 5, 7, 35

d

56

1, 2, 4, 7, 8, 14, 28, 56

e

78

1, 2, 3, 6, 13, 26, 39, 78

Chapter 1 | 1

SG Maths WB P6 Unit 01-06 not ans.indd 1

17/12/2021 3:11 PM

3. Determine if each of the following is a prime number. .g .

11 11 cannot be divided by 2, 3, 5 and 7 exactly.

11 has only 2 factors, 1 and 11.

So, 11 is a prime number.

b 37 37 cannot be divided by 2, 3, 5, 7, 11, 13, 17, 19 and 23.

37 has only 2 factors, 1 and 37.

So, 37 is a prime number.

a 26 26 ÷ 2 = 13 26 has more than 2 factors.

So, 26 is not a prime number.

c

35 35 ÷ 5 = 7 35 has more than 2 factors.

So, 35 is not a prime number.

4. List all the prime factors of each of the following. .g .

18 Factors of 18 = 1, 2, 3, 6, 9, 18 Prime factors of 18 = 2, 3

b 39 Factors of 39 = 1, 3, 13, 39 Prime factors of 39 = 3, 13

a 28 Factors of 28 = 1, 2, 4, 7, 14, 28 Prime factors of 18 = 2, 7

c

70 Factors of 70 = 1, 2, 5, 7, 10, 14, 35, 70 Prime factors of 70 = 2, 5, 7

2 | Mathematics Prathomsuksa 6

SG Maths WB P6 Unit 01-06 not ans.indd 2

17/12/2021 3:11 PM

5. Express the following numbers in the form of prime factorization using repeated short division. Express the answers in index notation. .g .

52

a 70

2 52 2 26 13 13 1

2 70 5 35 7 7 1

52 = 2 × 2 × 13 = 22 × 13

b 108

70 = 2 × 5 × 7

c

2 108 2 54 3 27 3 9 3 3 1

2 200 2 100 2 50 5 25 5 5 1

108 = 2 × 2 × 3 × 3 × 3 = 22 × 33 d 270 2 270 3 135 3 45 3 15 5 5 1 270 = 2 × 3 × 3 × 3 × 5 = 2 × 33 × 5

200

200 = 2 × 2 × 2 × 5 × 5 = 23 × 52 e

450 2 450 3 225 3 75 5 25 5 5 1 450 = 2 × 3 × 3 × 5 × 5 = 2 × 32 × 52 Chapter 1 | 3

SG Maths WB P6 Unit 01-06 not ans.indd 3

17/12/2021 3:11 PM

6. Express the following numbers in the form of prime factorization using factor tree. Express the answers in index notation. .g .

28

a 56

28 4

2

7

4

2

2

28 = 2 × 2 × 7 = 22 × 7

b 252

252 12

2

3

7

300

3

2

315

75 2

91 7

315 9

25 5

300 = 2 × 2 × 3 × 5 × 5 = 22 × 3 × 52

13

364 = 2 × 2 × 7 × 13 = 22 × 7 × 13

e

2

7

364

2

252 = 2 × 2 × 3 × 3 × 7 = 22 × 32 × 7

4

2

4

2

d 300

2

364

21 3

14

56 = 2 × 2 × 2 × 7 = 23 × 7

c

4

56

3 5

35 3

5

7

315 = 3 × 3 × 5 × 7 = 32 × 5 × 7

4 | Mathematics Prathomsuksa 6

SG Maths WB P6 Unit 01-06 not ans.indd 4

17/12/2021 3:11 PM

Practice 2

Highest common factor (HCF)

1. Determine if each of the following numbers is a common factor for the set of numbers in the brackets. .g .

4 (12 and 32) 12 ÷ 4 = 3 32 ÷ 4 = 8 So, 4 is a common factor for 12 and 32.

b 8 (40, 96 and 116) 40 ÷ 8 = 5 96 ÷ 8 = 12 116 ÷ 8 = 14 R 4 So, 8 is not a common factor for 40, 96 and 116.

a 6 (48 and 59) 48 ÷ 6 = 8 59 ÷ 6 = 9 R 5 So, 6 is not a common factor for 48 and 59.

c

13 (65, 91 and 143) 65 ÷ 13 = 5 91 ÷ 13 = 7 143 ÷ 13 = 11 So, 13 is a common factor for 65, 91 and 143.

2. List the common factors of the sets of numbers. .g .

6 and 30 Factors of 6 = 1, 2, 3, 6 Factors of 30 = 1, 2, 3, 5, 6, 10, 15, 30 So, common factors for 6 and 30 are 1, 2, 3 and 6.

a 52 and 78 Factors of 52 = 1, 2, 4, 13, 26, 52 Factors of 78 = 1, 2, 3, 6, 13, 26, 39, 78 So, common factors for 52 and 78 are 1, 2, 13 and 26.

Chapter 1 | 5

SG Maths WB P6 Unit 01-06 not ans.indd 5

17/12/2021 3:11 PM

b 66 and 102 Factors of 66 = 1, 2, 3, 6, 11, 22, 33, 66 Factors of 102 = 1, 2, 3, 6, 17, 34, 51, 102 So, common factors for 66 and 102 are 1, 2, 3 and 6.

c

28, 32 and 40 Factors of 28 = 1, 2, 4, 7, 14, 28 Factors of 32 = 1, 2, 4, 8, 16, 32 Factors of 40 = 1, 2, 4, 5, 8, 10, 20, 40 So, common factors for 28, 32 and 40 are 1, 2 and 4.

d 40, 56 and 88 Factors of 40 = 1, 2, 4, 5, 8, 10, 20, 40 Factors of 56 = 1, 2, 4, 7, 8, 14, 28, 56 Factors of 88 = 1, 2, 4, 8, 11, 22, 44, 88 So, common factors for 40, 56 and 88 are 1, 2, 4 and 8.

3. Circle the common factors of the numbers. .g .

66 and 120

2

4

3

6

a 20 and 80

5

4

10

7

b 38 and 80

4

3

8

2

c

20, 70 and 120

5

2

20

10

d 32, 96 and 140

2

3

4

8

6 | Mathematics Prathomsuksa 6

SG Maths WB P6 Unit 01-06 not ans.indd 6

17/12/2021 3:11 PM

4. Find the highest common factor (HCF) for each set of numbers. Use the repeated short division method. .g .

a 40 and 56

12 and 28 2 12 2 6 3

28 14 7

2 40 2 20 2 10 5

HCF of 12 and 28 = 2 × 2

=4

b 42 and 66 2 42 3 21 7

HCF of 40 and 56 = 2 × 2 × 2 =8

c 66 33 11

2 20 5 10 2

40 20 4

HCF of 20, 40 and 70 = 2 × 5

= 10

36 12 4 2

90 30 10 5

HCF of 18, 36 and 90 = 3 × 3 × 2

= 18

e 70 35 7

18, 36 and 90 3 18 3 6 2 2 1

HCF of 42 and 66 = 2 × 3 =6

d 20, 40 and 70

56 28 14 7

48, 60 and 102 2 48 3 24 8

60 30 10

102 51 17

HCF of 48, 60 and 102 = 2 × 3 =6

Chapter 1 | 7

SG Maths WB P6 Unit 01-06 not ans.indd 7

17/12/2021 3:11 PM