Workbook Prathomsuksa 5 © 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
BJRC365031_GoGetMaths WB Prelimpage P5.indd 1
885-87220-0363-0 First Published 2022
24/1/2565 BE 12:06
Contents Chapter 2
Chapter 2
Chapter 3
Chapter 4
Chapter 5
Chapter 6
Chapter 7
Revision 1
Content SG Maths WB P5 page ii.indd 2
Addition and subtraction 1 of fractions Practices
1
Think
16
Multiplication of fractions
17
Practices
17
Think
34
Division of fractions
Chapter 8
Chapter 9
Volume and capacity
115
Practices
115
Think
127
Perpendicular lines and 128 parallel lines Practices
128
Think
141
35
Quadrilaterals and prisms
142
Practices
35
Practices
142
Think
50
Think
155
Chapter 10
Chapter 11
Mixed operations of fractions
51
Perimeter and area of 156 quadrilaterals
Practices
51
Practices
156
Think
61
Think
166
Decimals
62
Practices
62
Bar graphs and line graphs
167
Think
79
Practices
167
Think
179
Percentages
80
Practices
80
Think
93
Units of length and mass
94
Practices
94
Think
103
Chapter 12
Revision 2
180
104
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Chapter 1 Addition and subtraction of fractions Practice 1
Fractions and division
1. Fill in the blanks. Express your answers as fractions. .g .
2 pizzas are divided equally among 3 children. What fraction of a pizza does each child get?
2÷3=
2 3
Each child gets
2 3
of a pizza.
a 3 chocolate bars are shared equally among 4 children. What fraction of a chocolate bar does each child get?
3÷4=
3 4
Each child gets
3 4
of a chocolate bar. Chapter 1 | 1
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b 3 pies are shared equally among 5 children. What fraction of a pie does each child get?
3÷5=
3 5
Each child gets
c
3 5
of a pie.
There are 7 pieces of biscuit. They are shared among 2 kids. What fraction of a piece of biscuit does each kid get?
7÷2=
7 2
Each child gets
7 2
of a piece of biscuit.
2 | Mathematics Prathomsuksa 5
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2. Fill in the blanks. Give your answers as fractions. .g .
A 3-m rope is cut into 4 pieces. How long is each piece of rope? 3m
14444444244444443
3÷4=
3 4
Each piece of rope is
3 4
m long.
a There is 5 kg of flour. The seller packs the flour into 8 packets. How much flour is there in each packet? 5 kg
14444444244444443
5÷8=
5 8
There is
5 8
kg of flour in each packet.
b There is 9 l of water in the tank. The water is poured equally into 5 pails. How much water is there in each pail? 9l
14444444244444443
9÷5=
9 5
There is
9 5
l of water in each pail. Chapter 1 | 3
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3. Divide. Express the answers as fractions in their simplest form. .g .
2÷5=
2 5
a 3÷7= 3 7
b 4÷6= 4 6
c
8 10
d 12 ÷ 22 = 12 22
=
4 5
7 ÷ 14 =
7 14
g 5 ÷ 20 = 5 20
1 2
8 ÷ 10 =
f
=
=
=
6 11
1 4
e
=
2 3
9 ÷ 15 =
9 15 3 5
=
h 6 ÷ 12 = 6 12
1 2
=
4. Divide. Express the answers as mixed numbers in their simplest form. .g .
4÷3=
4 3
a 5÷2 = 5 2 1 3
1 2
1 2
=1
c
18 5 3 =3 5
d 16 ÷ 6 = 16 6 4 =2 6 2 =2 3
24 5
g 14 ÷ 8 = 14 8 6 =1 8 3 =1 4
h 10 ÷ 4 = 10 4 2 =2 4 1 =2 2
18 ÷ 5 =
f
b 7÷2= 7 2
24 ÷ 5 =
=4
4 5
=2
=3
e
25 7 4 =3 7
25 ÷ 7 =
4 | Mathematics Prathomsuksa 5
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Practice 2
Comparing and ordering fractions
1. Compare the fractions. Fill in the blanks. .g .
3 and 2 5 3 3 = 5
9 15
10 15 So,
a
is greater than 2 3
10 15
7 = 9
14 18
.
is greater than
3 5
6 8
.
is greater than
3 4
.
3 and 7 4 8 3 = 4
6 8
7 8 So,
b
9 15
2 = 3
is greater than 7 8
.
5 and 7 6 9 5 = 6
15 18
14 18 So,
is smaller than 7 9
15 18
is smaller than
. 5 6
.
Chapter 1 | 5
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2. Which fraction is smaller? Show your workings. .g .
7 or 2 9 3
7 9
a 2 = 6 3 9
1 or 3 2 10
1 5 3 = 2 10 10
So, 2 is the smaller fraction. 3
So,
3 is the smaller fraction. 10
b 1 1 or 1 2 5 6
c
1 6 2 10 1 = 1 1 = 1 5 30 6 30
5 15 1 4 16 = 1 = = 4 12 3 3 12
So, 1
1 is the smaller fraction. 5
5 1 or 1 4 3
So,
5 is the smaller fraction. 4
3. Which fraction is greater? Show your workings. .g .
3 or 11 5 20
3 = 12 11 5 20 20
a 2 5 or 2 3 16 4 5 3 12 2 2 = 2 16 4 16
So, 3 is the greater fraction. 5
b
5 4 or 8 7
5 35 4 32 = = 8 56 7 56 So,
5 is the greater fraction. 8
So, 2
c
1
3 is the greater fraction. 4
8 or 1 13 9 18
8 16 13 1 = 1 1 9 18 18 So, 1
8 is the greater fraction. 9
6 | Mathematics Prathomsuksa 5
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4. Arrange the fractions. Show your workings. 4 5 1 (Starting with the smallest) 9 18 3 4 8 5 1 6 = = 9 18 18 3 18 .g .
Starting with the smallest: 5 , 1 , 4 18 3 9 a 11 2
10 6
7 (Starting with the greatest) 3
1 3 9 10 7 14 1 = = = 2 2 6 6 3 6 Starting with the greatest: b 22 5
12 3
8 3
7 10 1 , ,1 3 6 2
29 (Starting with the smallest) 15
2 12 36 2 5 25 8 40 29 2 = = 1 = = = 5 5 15 3 3 15 3 15 15 2 29 2 8 Starting with the smallest: 1 , , 2 , 3 15 5 3 c
1
5 6
13 12
7 3
15 12
13 (Starting with the greatest) 6
5 11 22 13 7 28 5 17 13 26 1 = = = 1 = = 6 6 12 12 3 12 12 12 6 12 Starting with the greatest: 11 5
d
9 4
75 40
2
7 13 5 5 13 , ,1 ,1 , 3 6 6 12 12
25 (Starting with the smallest) 10
11 88 9 90 75 80 25 100 = = 2 = = 5 40 4 40 40 40 10 40 Starting with the smallest:
75 11 9 25 , 2, , , 40 5 4 10 Chapter 1 | 7
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