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NS 2.2*1%7
Find the sum
or difference of two whole numbers up to three
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digits long.
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LQDGGLQJRUVXEWUDFWLQJWKUHHGLJLWQXPEHUVRQHDGGVRUVXEWUDFWVKXQGUHGVDQG
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UNDERLYING SKILLS AND CONCEPTS:
subtraction facts strategies;
model numbers;
place value
Regroup Tens to Subtract
a
K
ey Ide
You can use models to subtract with 2-digit and
3-digit numbers.
E x am p l E
Find the difference between 142 and 35.
142
! 35
Step 1: Show 142 with blocks.
100 !
40 !
2
100 !
30 ! 12
B – © CSL Associates, Inc. All rights reserved.
Step 2: Look at the ones.
You need to subtract 5.
Trade 1 ten for 10 ones.
Step 3: Now take away 35.
Step 4: How many are left?
100 and 7 more = 107
Chapter 11 – Lesson 3
100
!
7
page 127
Name
P RAC T I C E
Subtract.
132
24
2
149
46
108
4
103
150
33
5
6
121
172
35
8
9
112
■
■
345
39
306
147
35
137
534
26
508
162
41
117
7
3
272
36
236
■
■
10
135 – 20 115
11
179 – 70 109
12
246 – 30 216
13
286 – 60 226
Math
Reasoning
Number Sense
MR 2.3
Color the cards that show 148.
14
100 40 8
90 58
page 128
150 2
200 52
50 98
Chapter 11 – Lesson 3
B – © CSL Associates, Inc. All rights reserved.
1
Name
P RAC T I C E
Subtract.
146
38
2
168
38
108
4
130
130
27
5
6
111
151
24
8
9
112
■
■
234
28
206
186
74
127
526
16
510
173
62
103
7
3
243
25
218
■
■
10
169 – 60 109
11
145 – 30 115
12
286 – 70 216
13
248 – 20 228
Math
Reasoning
Number Sense
MR 2.3
Circle the cards that show 169.
14
100 60 9
170 1
90 69
page 86
200 31
50 119
Home Resource and Homework
Chapter 11 Lesson 3
B – © CSL Associates, Inc. All rights reserved.
1
MCX94TEG2Ch01_30.v9.4.1 2/19/01 19:47 Page 235
Name
P RAC T I C E
Subtract.
1
132
24
2
149
46
108
4
103
150
33
5
8
9
112
■
■
345
39
306
147
35
137
B – © CSL Associates, Inc. All rights reserved.
6
121
172
35
534
26
508
162
41
117
7
3
272
36
236
■
■
10
135 – 20 115
11
179 – 70 109
12
246 – 30 216
13
286 – 60 226
Math
Reasoning
Number Sense
MR 2.3
Color the cards that show 148.
14
100 40 8
150 2
90 58
Chapter 11 – Lesson 3
200 52
50 98
Student Book Page
page 128
Name
P RAC T I C E
Subtract.
146
38
2
168
38
108
4
130
130
27
5
6
111
151
24
8
9
112
■
■
234
28
206
186
74
127
526
16
510
173
62
103
7
3
243
25
218
■
■
10
169 – 60 109
11
145 – 30 115
12
286 – 70 216
13
248 – 20 228
Math
Reasoning
Number Sense
MR 2.3
Circle the cards that show 169.
14
100 60 9
170 1
90 69
page 86
200 31
50 119
Home Resource and Homework
Chapter 11 Lesson 3
B – © CSL Associates, Inc. All rights reserved.
1