2nd Edition
2A
Shaping Maths
Shaping Maths Activity Book
Part 1
Explore the world of Shaping Maths with Aini, Bala, Caili and David on their journey to the six fantastic Mathematics islands.
ACTIVITY BOOK
At each level, Shaping Maths offers a wide range of learning experiences, taking pupils from the concrete through the pictorial to the abstract mode of mathematical representation. Through clear presentation and a highly structured and spiral approach, the package provides pupils with a strong mathematical foundation and develops higher order thinking skills. Using a thematic approach, pupils are able to connect their everyday life experiences with Mathematics, thus encouraging active pupil participation and learning.
2nd Edition 2A Par t 1
Shaping Maths is an up-to-date instructional package designed to meet the learning needs of pupils from Primary 1 to 6. The Primary 2 package consists of two coursebooks, four activity books, and a teacher’s resource pack.
Shaping Maths makes Mathematics engaging, accessible and fun!
David
Caili
Bala
2A Part 1
Charlotte Collars • Koay Phong Lee • Lee Ngan Hoe • Tan Cheow Seng
Aini
ACTIVITY BOOK 2nd Edition
Charlotte Collars • Koay Phong Lee • Lee Ngan Hoe • Tan Cheow Seng
SMAB2A_Cover_pt1. 1
1/15/08 10:06:54 AM
ACTIVITY BOOK
2nd Edition
2A Part 1
BY
MINI
ST RY O F
E UC
D
D
A PPR
ON ATI
OV E
Charlotte Collars • Koay Phong Lee • Lee Ngan Hoe • Tan Cheow Seng (Cert. Ed.) (Ph.D.) (M.Sc.Ed.) (Cert. Ed.)
r
11
•
•
fo
us
-2 e f rom 2007
0
© 2007 Marshall Cavendish International (Singapore) Private Limited Published by Marshall Cavendish Education An imprint of Marshall Cavendish International (Singapore) Private Limited A member of Times Publishing Limited Times Centre, 1 New Industrial Road, Singapore 536196 Customer Service Hotline: (65) 6411 0820 E-mail:
[email protected] Website: www.marshallcavendish.com/education/sg First published 2007 Second impression 2008 Reprinted 2009 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior permission of the copyright owner. ISBN 978-981-01-6528-4 Edited by: Goh Jia Zhan and Yee Pey Ling Designed by: Henny Irawati Cover design by: Winnie Ng Printed in Singapore by C.O.S. Printers Pte Ltd
©981-01-6528-4.indd 1
1/11/08 5:29:56 PM
PREFACE Shaping Maths is an instructional package written according to the latest Primary Mathematics Syllabus provided by the Ministry of Education, Singapore. The package is designed to meet the learning needs of pupils from Primary 1 to 6. For Primary 2, the package consists of two coursebooks, four activity books and a teacher’s resource pack. Continuing research in education has resulted in the introduction of new features in the second edition. Through these features, educators are further equipped with various strategies in addressing teaching and learning needs. These features also include more open-ended questions to encourage exploration and in-depth thinking among pupils. Thus, mathematically inquisitive learners are born!
Features '+
Question Classification
– pre-requisite skills
– reinforcement of current concepts – higher-order thinking skills
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Contains reflection worksheets to develop pupils into self-regulated learners. *
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CO NT E NTS
1 Numbers to 1000 Looking Back − Tens and Ones Activity 1 1 Looking Back − Counting by Tens and Ones Activity 2 3 Counting Beyond 100 Activity 3 5 Hundreds, Tens and Ones Activity 4 9 Comparing and Ordering Numbers Activity 5 13 Activity 6 15 Let’s Find Out 17 2 Addition and Subtraction Within 1000 Meanings of Addition and Subtraction Activity 1 Addition Without Renaming Activity 2 Activity 3 Subtraction Without Renaming Activity 4 Activity 5 Addition With Renaming (1) Activity 6 Activity 7 Addition With Renaming (2) Activity 8 Activity 9 Subtraction With Renaming (1) Activity 10 Activity 11 Subtraction With Renaming (2) Activity 12 Activity 13
SMAB2A_Content_pt1 1
18
Solving Two-step Word Problems Activity 14 Let’s Find Out
40 42
3 Length Measuring Length in Metres Activity 1 Measuring Length in Centimetres Activity 2 Activity 3 Solving Word Problems Activity 4 Let’s Find Out
45 47
Review 1
54
My Maths Journal
67
43
50 53
21 23 24 26 27 29 30 32 34 36 37 39
3/30/07 11:11:16 AM
Unit 1
Activity 1 1
Count the tens and ones. Then fill in the missing numbers. a) b)
2
2
tens 8 ones = 28
tens 0 ones = 60
Colour the correct number of squares. Then fill in the missing numbers. a) b)
43 is 40 and 3 .
1
6
Numbers to 1000: Looking Back – Tens and Ones
33 is 30 and 3.
1
3
Write in numbers. Look at the example below. a) b)
es
6 tens 5 ones
9 on
65
89
c)
d) 0 ones 9 tens
10 tens
90
4
Write the numbers in words. Look at the example below. a) b)
7
2
fifty-two
70
seventy-seven
c)
d)
0
80
40
forty
SMAB2A_01_pt1. 2
0 ones
100
50
2
8 tens
6
eight-six
1
Numbers to 1000: Looking Back – Tens and Ones
10/23/06 11:07:59 AM
Unit 1
Activity 2 1
Complete these sentences.
a)
1 more than 35 is 36 .
35 + 1 = 36
b)
1 less than 35 is 34 .
35 – 1 = 34
Complete the number line.
2
7
1
17
27
37
57
67
a)
10 more than 47 is 57 .
47 + 10 = 57
b)
10 less than 47 is 37 .
47 – 10 = 37
Numbers to 1000: Looking Back – Counting by Tens and Ones
SMAB2A_01_pt1. 3
47
3
10/23/06 11:08:09 AM
3
Fill in the missing numbers. Look at the examples below. a)
56
1 more 45
10 less
55 10 more
65
1 less 54 b)
81
1 more 70
10 less
80 10 more
90
1 less 79
4
Circle the correct answers. Look at the example below.
+1
+1
a) 27
c)
28
SMAB2A_01_pt1. 4
63
73
+ 10
+ 10
–1
–1
40
30 – 10
4
b)
d) 100
99 – 10
1
Numbers to 1000: Looking Back – Counting by Tens and Ones
10/23/06 11:08:11 AM
Unit 1
Activity 3 1
Count and write the number in the box. Then write the number in words. a)
603
six hundred and three
460
four hundred and sixty
245
two hundred and forty-five
b)
c)
1
Numbers to 1000: Counting Beyond 100
5
2
a) 100 more than 354 is b) 100 less than 354 is 3
6
SMAB2A_01_pt1. 6
.
454 254
.
a) What number is 100 less than the given number? b) What number is 100 more than the given number?
a
b
100 less
100 more
322
422
600
700
719
819
1
522
800
919
Numbers to 1000: Counting Beyond 100
10/23/06 11:08:15 AM
4
a) Start at 216. Count on in tens. Colour the trail of tens in red. b) Start at 855. Count backwards in hundreds. Colour the trail of hundreds in blue.
845 855 B
835
755
320 220 219
825
655
516
217
236
316
226
216
A
805
815
400
555
416
218
795
116
196
155
255 455
355
246
256
136
266
156 176
276 286
c) Which mouse gets the cheese? Mouse
B
Which mouse reaches the mouse trap? Mouse A
1
Numbers to 1000: Counting Beyond 100
SMAB2A_01_pt1. 7
7
10/23/06 11:08:17 AM
5
Study the number line below. 190
6
200
a) What number is 1 more than 203?
204
b) What number is 10 less than 203?
193
a) Complete the number line below. 268
7
8
SMAB2A_01_pt1. 8
203
368
468
568
768
668
868
b) What number is 100 more than 568?
668
c) What number is 100 less than 568?
468
Study each number pattern and fill in the next two numbers. a)
88
188
288
388
488
b)
476
486
496
506
516
c)
760
750
740
730
720
d)
232
231
230
229
228
1
Numbers to 1000: Counting Beyond 100
10/23/06 11:08:19 AM
Unit 1
Activity 4 1
Count the hundreds, tens and ones. Then fill in the missing numbers. a)
3
hundreds 2
tens
3
ones =
323
6
hundreds 4
tens
0
ones =
640
7
hundreds 0 tens
7
ones =
707
b)
c)
1
Numbers to 1000: Hundreds, Tens and
SMAB2A_01_pt1. 9
9
10/23/06 11:08:23 AM
2
Match. 916
169
619
690
961 10
SMAB2A_01_pt1. 10
• •
Six hundred and nineteen
•
Six hundred and ninety
•
One hundred and sixty-nine
•
Nine hundred and sixty-one
•
•
•
• 1
Numbers to 1000: Hundreds, Tens and
10/23/06 11:08:26 AM
3
Write the numbers in words.
4
1
four hundred and eleven
411
five hundred and five
505
eight hundred and thirty-eight
838
Fill in the blanks. a) In 358, the digit
8
is in the ones place.
b) In 672, the digit
6
is in the hundreds place.
c) In 834, the digit
3
is in the tens place.
d) In 980, the digit
0
is in the ones place.
Numbers to 1000: Hundreds, Tens and
SMAB2A_01_pt1. 11
11
10/23/06 11:08:30 AM
5
Fill in the missing numbers. a) b) 213
200 + 10 +
327
3
c)
400
580
+ 40 + 9
500 +
e)
80
f) 7 4 6
638
600 + 30 + 8
hundreds tens ones
700 + 40 + 6
g)
h) 8 5 0
9 0 2
hundreds tens ones
800 + 50
SMAB2A_01_pt1. 12
+7
d) 449
12
20
300 +
hundreds tens ones 900 + 2
1
Numbers to 1000: Hundreds, Tens and
10/23/06 11:08:33 AM
Unit 1
Activity 5 1
a) What number does each picture show?
353
333
b) Which number is greater? 2
353
a) What number does each picture show?
240
153
b) Which number is smaller?
1
Numbers to 1000: Comparing and Ordering Numbers
SMAB2A_01_pt1. 13
153
13
10/23/06 11:08:38 AM
3
4
a) Write the correct answers in the boxes. 597 = 5
hundreds 9 tens
419 = 4
hundreds
508 = 5
hundreds 0 tens 8 ones
7
ones
tens 9 ones
1
b) Which number is the smallest?
419
c) Which number is the greatest?
597
Arrange these numbers in order. Begin with the greatest number. 437
409
432
437
432
409
greatest
5
Arrange these numbers in order. Begin with the smallest number. 308
298
306
275
275
298
306
308
smallest 14
SMAB2A_01_pt1. 14
1
Numbers to 1000: Comparing and Ordering Numbers
10/23/06 11:08:40 AM
Unit 1
Activity 6 You are given three cards:
1
1
6
8
a) Use these cards to form numbers between 100 and 1000. List all the possible numbers in the table below.
An example ➞
b) i)
Hundreds
Tens
Ones
1
6
8
1
8
6
6
1
8
6
8
1
8
1
6
8
6
1
Which two numbers have the greatest hundreds? 816, 861
ii) Between these two numbers, which is greater? 861
c) i)
Which two numbers have the smallest hundreds? 168, 186
ii) Between these two numbers, which is smaller? 168
d) Arrange the numbers listed in a) in order. Begin with the smallest number. 168, 186, 618, 681, 816, 861 1
Numbers to 1000: Comparing and Ordering Numbers
SMAB2A_01_pt1. 15
15
10/23/06 11:08:42 AM
2
You are given three cards. a) Write any number from 1 to 9 on the second and third cards. Answer varies
0 b) Use these three cards to form numbers between 100 and 1000. i) What is the greatest 3-digit number formed? Answer varies
ii) What is the smallest 3-digit number formed?
3
Answer varies
You are given four cards.
8
6
9
9
Use three of these cards to form numbers between 100 and 1000. a) What is the greatest 3-digit number formed? 998
b) What is the smallest 3-digit number formed? 689
16
SMAB2A_01_pt1. 16
1
Numbers to 1000: Comparing and Ordering Numbers
10/23/06 11:08:43 AM
Let’s Find Out
Number Riddle I am thinking of a 3-digit number. I can get the hundreds digit by adding the tens digit and the ones digit. The tens digit is 2 more than the ones digit. The ones digit is 2. What is the number that I am thinking of?
I shall find the answer by working backwards. 6
2
4
What is the tens digit? What is the hundreds digit?
1
Numbers to 1000: Let’s Find Out
SMAB2A_01_pt1. 17
17
10/23/06 11:08:45 AM
Unit 2
Activity 1 1
Fill in the missing number. a)
20 + 9 = 29 20
9 + 20 = 29
part
29 – 9 = 20 29 29 – 20 =
whole
9 part
b)
9
9 more than 20 is 29 . 20
is 9 less than 29.
50 + 7 = 57 50 part
7 + 50 = 57 57 – 50 =
57
7
57 – 7 = 50
whole
7
7 more than 50 is 57 .
part 50
18
SMAB2A_02_pt1..indd 18
is 7 less than 57.
2 Addition and Subtraction Within 1000: Meanings of Addition and Subtraction
10/23/06 11:59:45 AM
c) 40 + 10 = 50
40 part
10 + 40 = 50 50 – 40 =
50 whole
50 – 10 = 40 10 part
10 more than 40 is 50 . 40
2
10
is 10 less than 50.
Put ✓ next to the number sentence which matches the story. a) Mrs Muthu made 20 apple pies and 15 meat pies. How many pies did she make altogether? 20 + 15 = 35 20 – 15 = 5 Mrs Muthu made
35
pies altogether.
2 Addition and Subtraction Within 1000: Meanings of Addition and Subtraction
SMAB2A_02_pt1..indd 19
19
10/23/06 11:59:46 AM
b) Ali has 46 bookmarks. He gives 12 bookmarks to his friend. How many bookmarks has he left? 46 + 12 = 58 46 – 12 = 34 Ali has
34
bookmarks left.
c) Lin used 57 blue ribbons and 25 red ribbons. How many more blue ribbons than red ribbons did she use? 57 + 25 = 82 57 – 25 = 32 Lin used
32
more blue ribbons than red ribbons.
d) Aimin paid $25 for a dress. She had $24 left. How much money had she at first? $25 + $24 = $49 $25 – $24 = $1 She had $ 49
20
SMAB2A_02_pt1..indd 20
at first.
2 Addition and Subtraction Within 1000: Meanings of Addition and Subtraction
10/23/06 11:59:47 AM
Unit 2
Activity 2 1
63 + 120 =
183
63 +120 183
2
43 + 156 =
199
106 + 82 =
43 +156
106 + 82
1 9 9
1 8 8
30 + 431 =
461
215 + 763 =
3 0 +4 3 1
2 1 5 +7 6 3
4 6 1
9 7 8
2 Addition and Subtraction Within 1000: Addition Without Renaming
SMAB2A_02_pt1..indd 21
188
978
21
10/23/06 11:59:50 AM
3
a) Work out all the answers. Then colour the boxes where the answer is 568.
Mars
552 + 16 568
505 + 63
38 +540
5 6 8
5 7 8
163 +424
223 +345
364 +104
5 8 7
5 6 8
4 6 8 Jupiter
Saturn
257 +242
331 +237
441 +128
4 9 9
5 6 8
5 6 9
Neptune
b) Bala travelled along the path formed by the coloured boxes. Which planet did he land on? 22
SMAB2A_02_pt1..indd 22
Neptune
2 Addition and Subtraction Within 1000: Addition Without Renaming
10/23/06 11:59:52 AM
Unit 2
Activity 3 1
Mrs Chen sold 150 buns in the afternoon. She sold 127 buns in the evening. How many buns did she sell altogether?
150 + 127 =
She sold 2
277
277
2 7 7
buns altogether.
Devi has 214 beads. Her sister has 45 more beads than her. How many beads does Devi’s sister have?
Devi’s sister has 3
150 +127
259
beads.
Mr Lim spent $343. He had $125 left. How much money did he have at first?
He had $
468
at first.
2 Addition and Subtraction Within 1000: Addition Without Renaming
SMAB2A_02_pt1..indd 23
23
10/23/06 11:59:54 AM
Unit 2
Activity 4 1
358 – 125 =
233
358 –125 2 3 3
2
189 – 36 =
358 – 240 =
189 – 36
358 –240
1 5 3
1 1 8
879 – 259 =
24
153
620
909 – 403 =
8 7 9 –2 5 9
9 0 9 –4 0 3
6 2 0
5 0 6
118
506
2 Addition and Subtraction Within 1000: Subtraction Without Renaming
3
a) Work out all the answers. Then colour the boxes where the answer is 34. Greenland
194 –160 34
176 –142
258 – 34
3 4
2 2 4
168 –133
689 –655
889 –764
3 5
3 4
1 2 5
244 –110
339 –305
435 –401
1 3 4
3 4
3 4
China
Mali
Malaysia
b) Bala travelled along the path formed by the coloured boxes. Where did he land? Malaysia 2 Addition and Subtraction Within 1000: Subtraction Without Renaming
25
Unit 2
Activity 5 1
There were 476 people at a concert. 250 of them were adults. How many children were there? 476 – 250 =
226
476 –250 2 2 6
There were 2
SMAB2A_02_pt1..indd 26
110
toy soldiers.
Sally went shopping with $478. She bought a handbag and had $264 left. How much did she pay for the handbag?
She paid $ 26
children.
David has 168 toy soldiers. Tom has 58 fewer toy soldiers than David. How many toy soldiers does Tom have?
Tom has 3
226
214
for the handbag.
2 Addition and Subtraction Within 1000: Subtraction Without Renaming
10/23/06 12:00:02 PM
Unit 2
Activity 6 1
266 + 153 =
419
266 +153 4 1 9
2
67 + 125 =
192
159 + 70 =
67 +125
159 + 70
1 9 2
2 2 9
138 + 245 =
383
654 + 155 =
1 3 8 +2 4 5
6 5 4 + 1 5 5
3 8 3
8 0 9
2 Addition and Subtraction Within 1000: Addition With Renaming (1)
SMAB2A_02_pt1..indd 27
229
809
27
10/23/06 12:00:08 PM
3
Mark these addition sums. Put ✓ in the box if the answer is correct. Put ✗ in the box if the answer is wrong. Then show the correct way of adding. Sum
a)
How you should add
Correct answer
178 + 14 182
178 + 14
b)
252 + 18 270
252 + 18
252 + 18 =
c)
658 +129 777
658 +129
658 + 129 =
787
537 + 56 693
537 + 56
537 + 56 =
593
648 +190 848
648 +190
648 + 190 =
838
d)
e)
28
SMAB2A_02_pt1..indd 28
178 + 14 =
192
1 9 2
7 8 7
5 9 3
8 3 8
2 Addition and Subtraction Within 1000: Addition With Renaming (1)
10/23/06 12:00:09 PM
Unit 2
Activity 7 1
Mr Wu delivered 158 letters in the morning. He delivered 90 letters in the afternoon. How many letters did he deliver altogether? 158 + 90 =
158 + 90
248
2 4 8
He delivered 2
letters altogether.
Osman has 452 postcards. Aminah has 97 more postcards than Osman. How many postcards does Aminah have?
Aminah has 3
248
549
postcards.
247 women and 148 men work in a factory. How many workers are there in the factory?
There are
395
workers in the factory.
2 Addition and Subtraction Within 1000: Addition With Renaming (1)
SMAB2A_02_pt1..indd 29
29
10/23/06 12:00:11 PM
Unit 2
Activity 8 1
177 + 254 =
431
177 +254 4 3 1
2
87 + 635 =
722
87 +635
246 +575
7 2 2
8 2 1
528 + 96 =
30
SMAB2A_02_pt1..indd 30
246 + 575 =
624
398 + 409 =
5 2 8 + 9 6
3 8 9 +4 0 9
6 2 4
8 0 7
821
807
2 Addition and Subtraction Within 1000: Addition With Renaming (2)
10/23/06 12:00:15 PM
3
a) Add. 304 +396
536 +287
659 +254
7 0 0
8 2 3
9 1 3
435 +367
564 +269
384 +366
8 0 2
8 3 3
7 5 0
b) Help Mr Froggie cross the pond by colouring the leaves that match the answers above.
700 keep
903 room
650 tidy
750 clean
823 our 913 country
805 neat
833 and
733 or
802 green
c) Write down the message given on the coloured leaves. Keep our country clean and green. or Keep our country green and clean.
2 Addition and Subtraction Within 1000: Addition With Renaming (2)
SMAB2A_02_pt1..indd 31
31
10/23/06 12:00:20 PM
Unit 2
Activity 9 1
Mr Hamid bought a watch and a pair of shoes. How much did he spend altogether? $368 + $158 =
368 +158
526
5 2 6
He spent $ 2
526
altogether.
An oven costs $197 more than a toaster. What is the cost of the oven?
The cost of the oven is $ 3
SMAB2A_02_pt1..indd 32
.
Leo saved $346. Jenny saved $185 more than Leo. How much money did Jenny save?
Jenny saved $ 32
305
531
.
2 Addition and Subtraction Within 1000: Addition With Renaming (2)
10/23/06 12:00:22 PM
4
Bala had some stamps. He gave 159 stamps to David. He has 279 stamps left. How many stamps did Bala have at first?
Bala had 5
438
stamps at first.
Mrs Wang needs 350 blue beads, 265 red beads and 125 yellow beads to make a bag. How many beads does she need altogether? 350 265 +125 7 4 0
She needs 6
740
beads altogether.
Mr Soon had $112 left after buying a leather bag and a wallet. How much money did he have at first? $325
He had $
522
at first.
$85
2 Addition and Subtraction Within 1000: Addition With Renaming (2)
SMAB2A_02_pt1..indd 33
33
10/23/06 12:00:24 PM
Unit 2
Activity 10 1
416 – 233 =
183
416 –233 1 8 3
2
Subtract. 294 − 118 =
SMAB2A_02_pt1..indd 34
518 − 126 =
294 –118
518 –126
1 7 6
3 9 2
754 − 136 =
34
176
618
570 − 316 =
7 5 4 –1 3 6
5 7 0 –3 1 6
6 1 8
2 5 4
392
254
2 Addition and Subtraction Within 1000: Subtraction With Renaming (1)
10/23/06 12:00:27 PM
2 Addition and Subtraction Within 1000: Subtraction With Renaming (1)
SMAB2A_02_pt1..indd 35
35
10/23/06 12:00:28 PM
B
4 2 2
U
4 3 9
562 –123
O
U
L
Z
4 9 1
916 –425
L
D
3 9 8
679 –281
A
E
O
1 9 2
858 –666
R
Z
D
1 5 1
832 –681
422 192 439 151 491 137 253 455 398
B
L
4 9 1
867 –376
A
386 –249 137
71
“What do you call a sleeping bull?”
Use the codes at the bottom of the page to solve this riddle:
840 –418
3
E
2 5 3
781 –528
R
4 5 5
645 –190
Unit 2
Activity 11 1
There are 193 mangoes in a basket. 25 of them are green. How many mangoes are not green? 193 – 25 =
193 – 25
168
1 6 8 168
2
mangoes are not green.
Roy collected 250 phonecards. Helen collected 38 fewer phonecards than Roy. How many phonecards did Helen collect? 250 – 38 = 212
Helen collected 3
212
phonecards.
Meimei went shopping with $215. She spent $194. How much money did she have left? $215 – $194 = $21
She had $ 36
SMAB2A_02_pt1..indd 36
21
left.
2 Addition and Subtraction Within 1000: Subtraction With Renaming (1)
10/23/06 12:00:30 PM
Unit 2
Activity 12 1
215 – 186 =
29
215 –186 29
2
Subtract. 314 − 68 =
246
460 − 297 =
314 – 68
460 –297
2 4 6
1 6 3
657 − 268 =
389
703 − 425 =
6 5 7 –2 6 8
7 0 3 –4 2 5
3 8 9
2 7 8
2 Addition and Subtraction Within 1000: Subtraction With Renaming (2)
SMAB2A_02_pt1..indd 37
163
278
37
10/23/06 12:00:33 PM
38
SMAB2A_02_pt1..indd 38
2 Addition and Subtraction Within 1000: Subtraction With Renaming (2)
10/23/06 12:00:34 PM
3
E
7 5 6
941 –185
V
E
109 178 375 453 756
P
98
N
E
7 5 6
925 –169
O
V
4 5 3
722 –269
L
N
1 7 8
821 –643
L
9 8
621 –523 O
1 0 9
507 –398
“What is an 8-letter word that has only 1 letter in it?”
Use the codes at the bottom of the page to solve this riddle:
P
3 7 5
700 –325
E
7 5 6
900 –144
Unit 2
Activity 13 1
On Saturday, 353 people visited a food stall. On Sunday, 421 people visited the same stall. How many more people visited the stall on Sunday than on Saturday? 421 – 353 =
68
421 –353 6 8
68
more people visited the stall on Sunday than on Saturday. 2
Hassan sold 532 sticks of chicken satay. He sold 155 fewer sticks of mutton satay. How many sticks of mutton satay did he sell? 532 – 155 = 377
He sold 3
377
sticks of mutton satay.
There were 420 guests at a grand dinner. 245 of the guests wore ties. How many guests did not wear ties? 420 – 245 = 175
175
guests did not wear ties.
2 Addition and Subtraction Within 1000: Subtraction With Renaming (2)
SMAB2A_02_pt1..indd 39
39
10/23/06 12:00:35 PM
Unit 2
Activity 14 1
Mr Salleh paid $688 for a watch. He paid $520 less for a tie-pin than the watch. a) How much did he pay for the tie-pin? b) How much did he pay altogether for the watch and the tie-pin? (a) $688 – $520 = $168 (b) $688 + $168 = $856
a) He paid $
168
b) He paid $ 856
2
for the tie-pin. altogether.
Mr Lee used 135 m of cloth to make curtains. He used 67 m more to make cushion covers than the curtains. a) How much cloth did he use to make cushion covers? b) How much cloth did he use altogether to make curtains and cushion covers? (a) 135 + 67 = 202 (b) 135 + 202 = 337
202 m of cloth to a) He used make cushion covers.
b) He used 337 altogether. 40
SMAB2A_02_pt1..indd 40
m of cloth
2 Addition and Subtraction Within 1000: Solving Two-step Problems
10/23/06 12:00:37 PM
3
346 men, 264 women and 135 children took part in a fancy dress parade. a) How many adults took part? b) How many fewer children than adults took part? (a) 346 + 264 = 610 (b) 610 – 135 = 475
4
a)
610
b)
475
adults took part.
fewer children than adults took part.
Tom, Ali and Lam are bakers. Tom used 275 kg of flour this week. Ali used 18 kg less flour than Tom. Lam used 35 kg more flour than Tom. a) How much flour did Ali use? b) How much flour did Lam use? (a) 275 – 18 = 257 (b) 275 + 35 = 310
a) Ali used b) Lam used
257 310
kg of flour. kg of flour.
2 Addition and Subtraction Within 1000: Solving Two-step Problems
SMAB2A_02_pt1..indd 41
41
10/23/06 12:00:38 PM
Let’s Find Out
Faulty Calculator 1
When we add 345 and 123 using a calculator: Press 3
4
5
+
1
2
3
= .
What answer does the calculator show? 468
345 + 123 = 2
Bala has a faulty calculator. The 4 and 7 keys of his calculator cannot work. a) To add 345 and 123, Bala presses 3
3
5
+
1
0
+
1
2
3
=
Will he get the correct answer for ‘345 + 123’? Why? Yes. 335 + 10 + 123 = 468
b) Which buttons of the calculator should Bala press to find the value of ‘709 – 253’? Show two possible ways by filling in the boxes below.
42
SMAB2A_02_pt1..indd 42
8
0
9
−
1
0
0
−
8
0
9
−
3
5
3
=
2
5
3
=
2 Addition and Subtraction Within 1000: Let’s Find Out
10/23/06 12:00:40 PM
Unit 3
Activity 1 1
a) Use glue to join two open pages of old newspapers together. Place a metre ruler at the edge like this. metre ruler
b) Draw a strip 1 m long and cut it out using a pair of scissors. 1m
c) With your classmates, line the 1-m strips end-to-end along the length of the classroom to measure how long it is.
length of classroom
Answer varies
m.
The length of my classroom is about
d) Now put the strips on the floor along the corridor to find its length. Answer varies The length of the corridor is about
3 Length: Measuring Length in Metres
SMAB2A_03_pt1.indd 43
m.
43
10/23/06 12:11:49 PM
2
Work with a partner. First guess the answers. Then check your answers using a metre ruler or a 1-m string. Put ✓ in the correct boxes. Guess
Check
More than Less than More than Less than 1m 1m 1m 1m
44
My height
Answers vary
My arm’s length
Answers vary
My waistline
Answers vary 3 Length: Measuring Length in Metres
Unit 3
Activity 2 1
Fill in the blanks. 0
1
2
3
4
5
6
7
8
9
10 cm
A
B
C
D
a) Ribbon A is
7
cm long.
b) Ribbon B is
6
cm long.
c) Ribbon C is as long as Ribbon d) Ribbon D is
2
D
is the shortest.
f)
A
is the longest.
3 Length: Measuring Length in Centimetres
SMAB2A_03_pt1.indd 45
.
cm shorter than Ribbon A.
e) Ribbon Ribbon
B
45
10/23/06 12:11:53 PM
2
a) Use a ruler to measure the length and breadth of this bookmark. length:
10
cm
SHAPING MATHS
breadth:
b) The breadth of the bookmark is than the length. 3
7
3
cm
cm shorter
Collect these things. Measure their lengths using a ruler.
Answer varies
Stapler: about
cm
Answer varies
Pencil case: about Paper clip: about
cm
cm
Answer varies 46
SMAB2A_03_pt1.indd 46
3 Length: Measuring Length in Centimetres
10/23/06 12:11:59 PM
Unit 3
Activity 3 1
a) Estimate and then measure the length of each line.
G
B
A
D
C
E
F
Line
Estimate
Actual
AB
Answer varies
5 cm
CD
Answer varies
10 cm
EF
Answer varies
11 cm
GH
Answer varies
10 cm
H
b) Fill in the blanks. Line
CD
is as long as Line
GH .
Line EF is longer than Line CD by 3 Length: Measuring Length in Centimetres
SMAB2A_03_pt1.indd 47
1
cm. 47
10/23/06 12:12:01 PM
2
How long is each of these lines? Measure them using a string and a ruler. a) L
K
Line KL is
9
cm long.
b)
N M
Line MN is
3
10
cm long.
c) Line
MN
is longer than Line
KL .
d) Line
KL
is shorter than Line
MN .
a) Draw a straight line PQ 7 cm long. P
Q
b) Draw a straight line RS 2 cm longer than Line PQ. R
4
S
a) Draw a straight line WX 14 cm long. W
X
b) Draw a straight line YZ 4 cm shorter than Line WX. Y
48
SMAB2A_03_pt1.indd 48
Z
3 Length: Measuring Length in Centimetres
10/23/06 12:12:03 PM
5
Fill in the blanks with cm or m. a) The height of our school flagpole m
is about 5
.
b) The length of my thumb is about 3 c)
cm .
The height of my water bottle is about 20
d)
e)
I am about 10 cm than my sister.
shorter
I walk about 50 m from my school to the nearest bus-stop every day.
3 Length: Measuring Length in Centimetres
SMAB2A_03_pt1.indd 49
cm .
49
10/23/06 12:12:04 PM
Unit 3
Activity 4 1
Aini’s bear is 18 cm tall. Caili’s bear is 15 cm taller than Aini’s. How tall is Caili’s bear? 15 cm
+ ?
18 15 3 3
18 cm Aini’s bear
2
Caili’s bear
18 + 15 =
33
Caili’s bear is
33
cm tall.
The grey belt is 78 cm long. The black belt is 85 cm long. How much shorter is the grey belt than the black belt? 78 cm
?
85 – 78 7 85 cm
85 – 78 = The grey belt is the black belt.
50
SMAB2A_03_pt1.indd 50
7 7
cm shorter than
3 Length: Solving Word Problems
10/23/06 12:12:07 PM
3
David uses two strings to tie a parcel. The first string is 28 cm long. The second string is 35 cm long. What is the total length of the two strings? 28 + 35 = 63
The total length of the two strings is 63
4
cm.
Mr Hari bought a rope 150 m long. He used 95 m of it to fence his garden. What was the length of rope left? 150 – 95 = 55
The length of rope left was
3 Length: Solving Word Problems
SMAB2A_03_pt1.indd 51
55
m.
51
10/23/06 12:12:07 PM
5
Mrs Li used 168 m of cloth to make school uniforms. She had 32 m of cloth left. How much cloth did she have at first? 168 + 32 = 200
She had 6
200
m of cloth at first.
Three flags, A, B and C are placed along a straight line. The distance between Flag B and Flag C is 28 m. The distance between Flag A and Flag B is 30 m longer than that between Flag B and Flag C. What is the distance between Flag A and Flag C? A
B
C
28 + 30 = 58 58 + 28 = 86
The distance between Flag A and Flag C is
52
SMAB2A_03_pt1.indd 52
86
m.
3 Length: Solving Word Problems
10/23/06 12:12:08 PM
Let’s Find Out
Goldilocks and the Three Bears Goldilocks enters the bedroom of the three bears. She finds three beds.
The length of the longest bed is 180 cm. Mother Bear’s bed is 30 cm shorter than Father Bear’s bed and 50 cm longer than Baby Bear’s bed. a) How long is Mother Bear’s bed? 150 cm
b) How long is Baby Bear’s bed? 100 cm
c) Goldilocks is 160 cm tall. Which bed fits her best? Why? Father Bear’s bed
3 Length: Let’s Find Out
SMAB2A_03_pt1.indd 53
53
10/23/06 12:12:09 PM
Review 1 1
Count the tens and ones. Then fill in the missing numbers. a)
4
tens
5
ones = 45
5
tens
6
ones = 56
6
tens
0
ones = 60
b)
c)
54
Review 1
2
Fill in the missing numbers. a) 1 more than 54 is b) 10 more than 68 is c) 1 less than 45 is d) 10 less than 93 is
3
55
.
78 44 83
. . .
a) Write the numbers. Thirty-two
32
Forty-five
45
b) Write the numbers in words.
4
Review 1
Sixty-nine
69
Eighty-seven
87
In 496, the digit a)
6
is in the ones place.
b)
9
is in the tens place.
c)
4
is in the hundreds place. 55
5
Fill in the missing numbers. 223
a) 100 more than 123 is b) 100 less than 635 is
535
.
c) 100 less than 656 is
556
.
d) 100 more than 379 is 6
7
479
.
Study each number pattern and fill in the missing numbers. a)
67
77
87
97
107
b)
132
232
332
432
532
c)
384
374
364
354
344
d)
429
428
427
426
425
Fill in the missing numbers. a) 400 + 20 + 5 = b) 600 +
80
d) 200 + e)
700
50
425
+ 1 = 681
c) 900 + 90 + 9 =
56
.
999
+ 3 = 253
+ 60 + 5 = 765 Review 1
8
9
10
Write the numbers. a) Three hundred and five
305
b) Five hundred and twenty-four
524
c) Seven hundred and fifty-nine
759
d) Eight hundred and sixty-one
861
Write the numbers in words. a)
308
Three hundred and eight
b)
530
Five hundred and thirty
c)
648
Six hundred and forty-eight
d)
819
Eight hundred and nineteen
a) Arrange these numbers in order. Begin with the smallest number. 506
500
539
521
500
506
521
539
smallest Review 1
57
b) Arrange these numbers in order. Begin with the greatest number. 708
718
780
735
780
735
718
708
greatest
11
Arrange these three cards
2
1
3
to form:
a) the greatest 3-digit number 3
2
1
b) the smallest 3-digit number 1
12
2
3
Fill in the missing numbers. 80 + 7 = 87 80
87 – 7 = 80 7 + 80 = 87
87 7
87 – 80 =
7
7 more than 80 is 87 . 7 less than 87 is 80 . 58
Review 1
13
Add. a) 204 + 75 =
b) 342 + 257 =
20 4 + 7 5
34 2 + 25 7
2 7 9
5 9 9
c) 654 + 18 =
672
d) 357 + 64 =
65 4 + 1 8
35 7 + 6 4
6 7 2
4 2 1
e) 284 + 179 =
463
f)
67 + 598 =
2 8 4 + 1 7 9
6 7 +5 9 8
4 6 3
6 6 5
g) 719 + 185 =
Review 1
279
904
h) 138 + 262 =
7 1 9 +1 8 5
1 3 8 +2 6 2
9 0 4
4 0 0
599
421
665
400
59
14
Subtract. a) 198 – 52 =
b) 364 – 143 =
19 8 – 5 2
36 4 – 14 3
1 4 6
2 2 1
c) 560 – 234 =
326
d) 735 – 307 =
56 0 – 2 3 4
73 5 – 30 7
3 2 6
4 2 8
e) 613 – 264 =
349
f)
750 – 268 =
6 1 3 – 2 6 4
7 5 0 –2 6 8
3 4 9
4 8 2
g) 832 – 748 =
60
146
84
h) 400 – 265 =
8 3 2 –7 4 8
4 0 0 –2 6 5
8 4
1 3 5
221
428
482
135
Review 1
15
Add. a) 345 + 123 + 66 =
534
345 123 + 66 5 3 4
b) 45 + 236 + 459 =
740
45 236 + 459 7 4 0
16
After spending $175 on a watch, Julie was left with $90. How much money did she have at first? $175 + $90 = $265
She had $ 17
265
at first.
524 people were at the school carnival. 452 of them were children. The rest were adults. How many adults were there? 524 – 452 = 72
There were Review 1
72
adults. 61
18
Jane has 162 stickers. Meiling has 58 more stickers than Jane. How many stickers does Meiling have? 162 + 58 = 220
220
Meiling has 19
stickers.
Mr Lin has $510. He spends $387 on a printer. How much money does he have left? $510 – $387 = $123
He has $ 20
123
left.
There are 528 Primary Two pupils in the school. There are 164 more Primary Two pupils than Primary One pupils. How many Primary One pupils are there? 528 – 164 = 364
There are 62
364
Primary One pupils. Review 1
21
There were 256 boys, 224 girls and 85 adults at a concert. a) How many children were there at the concert? b) How many more children than adults were there? a) 256 + 224 = 480 b) 480 – 85 = 395
22
a) There were concert.
480
children at the
b) There were than adults.
395
more children
Fatimah prepared 370 sticks of mutton satay. She prepared 250 fewer sticks of mutton than chicken satay. a) How many sticks of chicken satay did she prepare? b) How many sticks of satay did she prepare altogether? a) 370 + 250 = 620 b) 620 + 370 = 990
a) She prepared 620 chicken satay. b) She prepared altogether. Review 1
990
sticks of sticks of satay 63
23
Fill in the blanks.
White tape Black tape
a) The length of the white tape is
6
cm.
b) The length of the black tape is
8
cm.
c) The total length of the two tapes is d) The black tape is white tape. 24
cm.
cm longer than the
Which line is longer, PQ or RS? P
Q
R
S
Guess:
PQ
Check:
PQ =
10
cm
RS =
8
cm
PQ 64
2
14
is longer than
is longer than
RS .
RS . Review 1
25
a) Draw a straight line AB 5 cm long. A
B
b) Draw a straight line CD 3 cm longer than Line AB. A
26
B
Fill in the blanks with cm or m. a) Daddy’s height is about 174
cm .
b) The length of our school field is about 120 c) The length of a pencil is about 18 d) The width of the hall is about 20
m
.
cm . m
.
27 Mother’s foot
My foot
a) My foot is about
15
b) Mother’s foot is about c) My foot is Review 1
7
cm long. 22
cm long.
cm shorter than Mother’s foot. 65
28
Mrs Crawford used 85 m of lace to make curtains. She had 28 m of lace left. How much lace did she have at first? 85 + 28 = 113
She had 29
113
m of lace at first.
Isa uses two ribbons to tie presents. The first ribbon is 242 cm long. The second ribbon is 187 cm long. How much longer is the first ribbon than the second? 242 – 187 = 55
55 The first ribbon is than the second ribbon.
29 30
cm longer
Ahmad is 95 cm tall. Ban Lee is 16 cm taller than Ahmad. Charles is 10 cm shorter than Ban Lee. How tall is Charles? 95 + 16 = 111 111 – 10 = 101
Charles is 66
101
cm tall. Review 1
