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New Jersey Center for Teaching and Learning
Progressive Mathematics Initiative
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2nd Grade
2 digit Addition &
Subtraction
2012-12-10
www.njctl.org
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Table of Contents
2 Digit Addition & Subtraction
Mentally adding and subtracting 10 and 100
Addition
Subtraction
Mixed Practice
click on a
topic to go to
that section
Mentally Adding and Subtracting 10 and 100
Mentally Adding 10
click on a topic to
go to that section
Mentally Subtracting 10
Review Adding and Subtracting 10
Adding and Subtracting 100
Review Adding and Subtracting 10 and 100
Return to
Table of Contents
Mentally Adding 10
click to go back to
table of contents
Count by 10s
Write the numbers
What digit is changing as you count?
What number is this?
Add ten more and what
number does it become?
110 + 10 = 120
Count by 10s
340, 350, ___, ___, ___, ___
What number comes next?
___
Count by 10s
648, 658, ___, ___, ___, ___
What number comes next?
___
What number is 10 more?
247
530
162
493
781
333
What is 10 more than 990?
Add 10 to each number.
85
126
369
475
637
790
294
541
829
105
227
352
400
58
511
638
795
823
1
10 more than 390 is 490.
Yes
No
2
10 more than 567 is 577.
Yes
No
3
10 more than 142 is 153.
Yes
No
4
What is 10 more than this number?
5
What is 10 more than this number?
6
612 + 10 = ?
7
What is 10 more than 893?
8
187 + 10 = ?
Mentally Subtracting 10
click to go back to
table of contents
What number is shown?
Count back by 10s.
180, 170, ___, ___, ___, ___, ___
Count back by 10s.
260, 250, ___, ___, ___, ___, ___
What number comes next?
___
Count back by 10s.
557, 547, ___, ___, ___, ___
What number comes next?
___
What number is 10 less?
631
290
444
148
525
317
Subtract 10 from each number.
85
126
369
475
637
790
294
541
829
105
227
352
400
58
511
638
795
823
9
10 less than 384 is 374
Yes
No
10
10 less than 516 is 515
Yes
No
11
10 less than 240 is 140
Yes
No
12
What is 10 less than this number?
13
What is 10 less than this number?
14
621 - 10 =
15
308 - 10 =
16
975
- 10
Review adding and
subtracting 10
click to go back to
table of contents
When you add 10
the tens place goes
UP one digit.
Once you count up to
9 in the tens place, that
digit becomes a 0 and
the hundreds place goes
up ONE digit. The ones
place stays the same.
click for an example
152
+ 10 = 162
click for
an example
294
+ 10
= 304
When you subract 10
the tens place down
one digit.
Once you count down
to 0 in the ones place,
that digit becomes a 9
and the hundreds place
goes down ONE digit.
The ones place stays
the same.
click for an example
385 - 10 = 375
click -for10
an =
example
609
599
Move the numbers into the correct place.
10 more
10 less
228
238
316
381
391
119
129
139
804
460
794
480
296
582
602
470
592
814
248
401
306
Target
Number
173
183
10 more
10 less
266
256
10 more
10 less
304
294
10 more
10 less
482
492
10 more
10 less
507
497
10 more
10 less
693
703
10 more
10 less
724
714
10 more
10 less
831
841
10 more
10 less
989
999
10 more
10 less
1005
995
10 more
10 less
17
Is 346, 10 more or 10 less than 336?
A
10 more
B
10 less
18
Is 802, 10 more or 10 less than 792?
A
10 more
B
10 less
19
What is 10 less than 518?
20
What is 10 more than 496?
21
What is 10 more than 747?
22
What is 10 less than 205?
Adding and Subtracting 100
click to go back to
table of contents
click each box
for a question
When we add or subtract 10 to a number,
what place value ALWAYS stays the same?
When does the hundreds place change
when adding 10?
When does the hundreds place
change when subtracting 10?
What number does this show?
326 + 100 = 426
What place value changed
when 100 was added?
How did it change?
What number does this show?
547 - 100 = 447
What place value changed
when 100 was subtracted?
How did it change?
How many hundreds
are here?
What will happen
if I add one more?
10 hundreds is the same as 1 thousand or 1,000
When 100 is added or subtracted the
tens and ones places stay the same.
If 100 is added, how does
click
the hundreds place change?
If 100 is subtracted,
click how does
the hundreds place change?
23
100 more than 592 is 692
Yes
No
24
100 less than 364 is 354
Yes
No
25
What is 100 more than 681?
26
What is 100 less than 204?
27
What is 100 more than 127?
28
What is 100 less than 923?
Review adding and
subtracting 10 and 100
click to go back to
table of contents
click each box for a question
When adding or subtracting 100,
what place value stays the same?
What place value or values change when
adding or subtracting 100?
When adding or subtracting 10,
what place value stays the same?
When adding or subtracting 10,
what place value or values changes and
when?
Use the base 10 blocks to
show 10 more than 372
Use the base 10 blocks to
show 10 more than 594
Use the base 10 blocks to
show 10 more than 403
Use the base 10 blocks to
show 10 more than 285
Use the base 10 blocks to
show 100 more than 147
Use the base 10 blocks to
show 100 more than 320
Use the base 10 blocks to
show 100 more than 609
Use the base 10 blocks to
show 100 more than 168
100
Less
338
10
Less
428
Target
Number
10
More
438
448
527
175
396
651
100
More
538
29
What is 100 more than 39?
30
What is 10 less than 726?
31
What is 10 more than 509?
32
What is 100 less than 224?
33
What is 10 more AND 100 more than 142?
34
What is 10 less AND 100 less than 317?
click to go to
the section
Addition
2 Digit Addition with Number Grid
Addition with Base 10 Blocks
2 Digit Addition
2 Digit Addition with Regrouping
Adding 3 and 4 2-digit numbers
click to return to main
table of contents
2 Digit Addition with Number Grid
click to return to
Addition table of contents
There were 52 green apples in the basket
and 31 red apples. How many apples were
there all together?
How can we
use the
number grid
to solve this
problem?
52 + 31
When adding larger
numbers on the grid
start with the larger
number. Count by
tens, then ones.
How many tens are in
31?
41
+ 18
When adding larger
numbers on the grid
start with the larger
number. Count by
tens, then ones.
23 + 34 =
When adding larger
numbers on the grid
start with the larger
number. Count by
tens, then ones.
62
+ 35
When adding larger
numbers on the grid
start with the larger
number. Count by
tens, then ones.
35
85 + 14 =
A
98
B
99
C
89
D
95
36
54 + 22
A
74
B
72
C
76
D
34
37
73
+ 13
38
24
+ 21
39
21 + 47 =
Addition with Base 10 Blocks
click to return to
addition table of contents
35 + 23 =
Tens
Ones
17
+ 42
Tens
Ones
58 + 40 =
Tens
Ones
26
+ 31
Tens
Ones
40
62 + 36 =
41
73
+ 11
42
84 + 5 =
43
33
+ 46
44
24 + 70 =
2 Digit Addition
click to return to
addition table of contents
When adding 2 digit addends using
paper and pencil it is VERY IMPORTANT
to line up your addends correctly!!
65 + 32
Tens
The ones must be lined up
and the tens must be lined up.
6 5
+ 3 2
+
Ones
6
5
3
2
Once the problem
is lined up correctly, add
the ones column first.
Tens
+
Ones
6
3
5
2
After you add the ones,
add the tens column.
Tens
+
Ones
6
3
5
2
7
65
+ 32
97
Let's try another one
Tens
2 6
+ 5 3
Ones
Practice
+
4
6
4
2
Tens
Ones
Practice
75
+
4
Tens
Ones
Add without using
the tens and ones
chart.
61
+ 22
Add without using
the tens and ones
chart.
11 + 31 =
52
+ 22
22
+ 54
53
+ 22
41
+ 15
13
+ 42
33
+ 21
45
26 + 71 =
46
84
+ 12
47
25
+ 23
48
34 + 54 =
49
15 + 34 =
Problem Solving
with Addition
Rob picked 17 blueberries and
12 strawberries. How many
berries did Rob pick?
What numbers
will go in the
chart?
_____ berries
Tens
Ones
Will read 6 pages of his book
on Monday. On Tuesday, he
read double the amount of
pages. How many pages did
he read in all?
What numbers
will go in the
chart?
_____ pages
Tens
Ones
Jake planted 22 tomato plants
in his front yard and 16 in his
backyard. How many tomato
plants did Jake plant in all?
What numbers
will go in the
chart?
_____ plants
Tens
Ones
Nathan saved 65 cents. This
week he will save 12 cents.
How much money will he
have then?
What numbers
will go in the
chart?
_____ cents
Tens
Ones
50
James buys two coupon books. Each book has
24 coupons. How many coupons does he buy?
A
22
B
24
C
44
D
48
51
Which is the sum?
22 + 61 =
A
41
B
68
C
83
D
74
52
Ms. Johnson's class has a fish tank with 15 red
fish and 24 black fish. How many fish are in the
tank?
53
The soccer team sold 38 white shirts and 50
blue shirts. How many shirts did they sell in all?
54
In Mr. Smith's class there are 7 girls and 12
boys. How many children are in Mr. Smith's
class?
A
5
B
82
C
19
D
91
2 Digit Addition
with Regrouping
click to return to
addition table of contents
Regrouping with
base 10 blocks
36 + 27 =
Tens
Ones
Practice
46 + 29 =
Tens
Ones
Practice
72
+ 19
Tens
Ones
Practice
17 + 23 =
Tens
Ones
Practice
25
+ 47
Tens
Ones
Click on the picture below for more practice on
The National Library of Virtual Manipulatives Site
Change the columns to
2 prior to
starting
55
32 + 59 =
56
37
+ 48
57
58 + 18 =
58
27
+ 14
58
47 + 43 =
2 Digit Addition with Regrouping
tens
ones
2 5
+ 2 8
Add the ones first
5+8=
tens
ones
2 5
+2 8
5+8=
1 3
tens
ones
tens
ones
1
Now add
these 3
numbers
2 5
+ 2 8
3
tens
ones
1
2 5
+ 2 8
5 3
Let's Practice
tens
ones
4 2
+1 9
Which numbers
do we add first?
Let's Practice
tens
ones
1
4 2
+ 1 9
1
Now what do
we do?
Let's Practice
If the problem is
written this way,
rewrite the
problem to make
it easier to add.
3 6 + 1 8
tens
+
ones
Let's Practice
29
+ 44
Let's Practice
18 + 52 =
Roll 2 sets of dice and then add the numbers.
______
______
+
______
______
60
57 + 38 =
61
49
+ 24
62
56
+ 28
63
48 + 26 =
64
39
+ 33
Problem Solving with Addition
16 boys ride their bikes to school.
18 girls ride their bikes to school.
How many bikes are ridden to school?
tens
ones
16
+1 8
How do we add
these numbers?
Rich reads 26 pages.
Mike reads 37 pages.
How many pages did Rich and Mike read?
tens
ones
26
+3 7
24 frogs in the water.
43 frogs hopping on land.
How many frogs in all?
tens
ones
24
+4 3
Why don't we have
to regroup for this
problem?
Taylor counts 46 stars.
Morgan counts 39 stars.
How many stars did they count?
46
+ 39
Liam has 29 golf balls.
Ryan has 43 golf balls.
How many golf balls do they have?
29 + 43 =
What can we
do to make this
problem easier
to add?
65
Tracy ran in 26 races. Kaylee ran in 14 races. How
many races did they run?
A
30
B
31
C
41
D
40
66
There are 44 rows of corn in a field. There are 53
rows of corn in another field. How many rows of
corn in all?
A
98
B
97
C
107
D
87
67
Steve sees 36 birds. Jack sees 28 birds. How
many birds do they see?
68
Tim has 63 nickels. Olivia has 29 nickels. How
many nickels do they have?
69
Debbie sees 48 monkeys at the zoo. Brenda
sees 35 different monkeys. How many monkeys
did they see?
70
Debbie sees 48 monkeys at the zoo. Brenda sees
35 different monkeys. How many monkeys did
they see?
Addition into hundreds
with regrouping
Add:
63 + 52
How many ones?
How many tens?
Add:
63 + 52
11 tens
5 ones =
Add:
63 + 52
What can we trade
these 10 longs for?
Add:
63 + 52
What number is this?
When you add the tens place
and the answer is a 2 digit sum,
you must trade in for a hundred.
1. Always add the ones
first.
H
T
O
2. Ask: Do I regroup?
+
63
52
Do we have to regroup?
How do we know if we
have to regroup?
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
+
T
O
63
52
5
4. Ask: Do I regroup?
5. Add the hundreds.
Do we have to regroup?
To regroup from the tens
place into the hundreds:
H
+
T
O
63
52
5
6+5=
11
Look at your sum.
The number in the ones place
goes in the tens column. The
number in the tens place is
regrouped into the hundreds
column.
Now add the hundreds place.
H
1
+
T
O
6 3
5 2
15
H
1
T
O
6 3
+ 5 2
1 1 5
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
H
T
O
5. Add the hundreds.
+
8 4
5 7
1. Always add the ones first.
2. Ask: Do I regroup?
4 + 7 = 11
3. Add the tens.
4. Ask: Do I regroup?
H
T
O
5. Add the hundreds.
+
8 4
5 7
1. Always add the ones first.
1+8+5=
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
H
T
O
1
5. Add the hundreds.
+
8 4
5 7
1
1. Always add the ones first.
1+8+5=14
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
H
T
O
1
5. Add the hundreds.
+
8 4
5 7
1
1. Always add the ones first.
1+0=
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
H
5. Add the hundreds.
1 1
+
T
O
8 4
5 7
4 1
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
H
T
O
5. Add the hundreds.
+
7 7
9 0
1. Always add the ones first.
45
2. Ask: Do I regroup?
+64
3. Add the tens.
4. Ask: Do I regroup?
H
5. Add the hundreds.
+
T
O
71
99
+ 40
A
59
B
109
C
149
D
139
72
86 + 36 =
A
102
B
122
C
112
D
132
73
71 + 68 =
74
59
+ 32
75
85
+ 88
Review 2 digit Addition
There are 34 people on the train. 27
more people get on.
How many people are on the train now?
How can we write
this problem to
make it easier to add?
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
34
+ 27
Jeff's team scored 84 points.
Marc's team scored 68 points.
How many points did they score
all together?
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
84
+ 68
Shelby had 32 dollars.
Jasmine had 57 dollars.
How many dollars did they
have all together?
How will you
write this problem?
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
Angelo put 63 nails in the board,
then he put 44 more nails in the board.
How many nails did he put in all together?
How will you
write this problem?
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
76
Maria sold 47 tickets. Roger sold 23 tickets. How
many tickets did they sell all together?
A
60
B
24
C
70
D
160
77
There are 72 red roses and 65 pink roses. How
many roses all together?
A
137
B
147
C
37
D
127
78
Sophia had 56 stickers. She got 20 more. How
many stickers does she have now?
79
75 bees were in the nests. 75 more flew in. How
many are in the nest now?
80
Mrs. Field's room had 38 desks. Mrs. Scott's
room had 15 desks. How many desks do they
have all together?
81
The tree had 96 green leaves and 47 brown
leaves. How many leaves all together?
Adding 3 and 4 2-digit numbers
click to return to
addition table of contents
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
4 2
1 5
3 4
1. Always add the ones first.
2+5+4=
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
11
O
4 2
1 5
3 4
1. Always add the ones first.
How many numbers
am I adding?
2. Ask: Do I regroup?
3. Add the tens.
H
T
O
1
4. Ask: Do I regroup?
5. Add the hundreds.
+
4 2
1 5
3 4
1
1. Always add the ones first.
1+4+1+3= 9
2. Ask: Do I regroup?
3. Add the tens.
H
T
O
1
4. Ask: Do I regroup?
5. Add the hundreds.
+
4 2
1 5
3 4
1
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
3 4
2 3
1 4
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
4 7
5 6
8 2
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
1 3
6 8
4 5
82
54 + 3 + 15
A
99
B
619
C
72
D
585
83
42
93
+ 37
A
170
B
162
C
172
D
1512
84
45 + 13 + 29 =
85
32
46
+ 21
86
84
9
+ 76
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
1 2
3 4
6
2 1
1. Always add the ones first.
2+4+6+1= 1 3
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
1 2
3 4
6
2 1
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
T
O
4. Ask: Do I regroup?
1
5. Add the hundreds.
1 2
3 4
6
2 1
+
3
1. Always add the ones first.
1+1+3+2= 7
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
H
T
O
1
1 2
3 4
6
+ 2 1
3
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
H
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
2 7
1 5
4 2
8
1. Always add the ones first.
7+5+2+8= 2 2
2. Ask: Do I regroup?
3. Add the tens.
What do we
do now?
4. Ask: Do I regroup?
5. Add the hundreds.
H
+
T
O
2 7
1 5
4 2
8
1. Always add the ones first.
2+2+1+4=
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
H
T
O
2
2 7
1 5
4 2
+
8
2
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
H
T
O
2
2 7
1 5
4 2
+
8
9 2
H
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
T
8
3
1
+ 2
O
7
0
9
3
How do we line these numbers up?
94 + 67+ 2 + 48
H
1. Always add the ones first.
2. Ask: Do I regroup?
3. Add the tens.
4. Ask: Do I regroup?
5. Add the hundreds.
+
T
O
87
11
38
74
+ 25
88
31 + 15 + 20 + 2 =
A
68
B
86
C
347
D
50
89
23 + 36 + 57 + 10 =
90
17
24
50
+ 41
A
87
B
82
C
132
D
142
91
63
29
55
+ 48
click on a
topic to go to
that section
Subtraction
2 Digit Subtraction without Regrouping
Subtraction with Regrouping
Subtraction Word Problems with Regrouping
Subtraction Practice
click to return to main
table of contents
2-Digit Subtraction
Without Regrouping
Click to return to
subtraction table
of contents
What number is shown?
27
Now we want to subtract 14.
When we subtract, we take away.
ALWAYS start with the bigger
number when you subtract.
First, cross out the ones.
tens
ones
2 7
-1 4
How many are left?
Next, cross out the tens.
tens
ones
2 7
-1 4
3
How many are left?
tens
ones
2 7
-1 4
1 3
What number is shown?
What number is shown?
32
Let's subtract 20
Our subtract number model is:
32 - 20 =
We want to rewrite it
to make it easier to
subtract.
First, cross out the ones.
tens
ones
3 2
-2 0
How many are left?
Next, cross out the tens.
tens
ones
3 2
-2 0
2
How many are left?
tens
ones
3 2
-2 0
1 2
What do we do first?
85
- 62
Now what do we do?
85
- 62
3
What is the answer?
85
- 62
23
Cross out the ones.
Subtract ones.
Cross out tens.
Subtract tens.
76
- 26
What should we do to this subtraction
problem to make it easier to answer?
68 - 24 =
Cross out the ones.
Subtract ones.
Cross out tens.
Subtract tens.
68
- 24
92
If you take away 70, is the answer 24?
Yes
No
93
If you take 12 away from this number, is the
difference 7?
Yes
No
94
Take away 83. What is the difference?
95
Take 32 away from this number, what is the
difference?
96
What is the difference 67 - 47 = ?
2 Digit Subtraction without
regrouping - word problems
There are 24 children in a play. 11 children dance.
The other children sing. How many children sing?
24 children
There are 24 children in a play. 11 children dance.
The other children sing. How many children sing?
How many singers?
11 dancers
24 children
To find the difference, subtract:
24
- 11
Remember:
1. Subtract the ones
2. Subtract the tens
Number model:
24 - 11 = 13
or
24
- 11
13
The bigger number ALWAYS goes first!
There are 37 chairs at the play.
There are 13 couches.
How many more chairs than
couches are there?
How can we find
the answer?
13 couches
Difference
?
37 chairs
1. Subtract the ones
37
- 11
2. Subtract the tens
Zachary sold 28 tickets for the play.
Patrick sold 15 tickets. How many
more tickets did Zachary sell than Patrick?
On Friday, 49 people came to the play. On
Saturday, 25 fewer people came. How many
came on Saturday?
97
There are 28 girls and 16 boys in the class. How
many more girls than boys are in the class?
A
12
B
14
C
36
D
46
98
Britney sold 39 boxes of popcorn and 18 sodas.
How many more boxes of popcorn than sodas
did she sell?
A
11
B
18
C
21
D
26
99
There are 34 geese and 24 ducks in a pond.
How many more geese than ducks are there?
100
There are 41 seagulls on the beach. Then 30 fly
away. How many are left?
101
Henry has 45 stamps. He gives 13 to Julie. How
many stamps does he have left?
Subtraction with Regrouping
Click to return to
subtraction table
of contents
What number is shown?
What number is shown?
33
Now we want to subtract 18.
What do we do first?
33
- 18
We have to take 8 ones away,
but we do not have enough.
Trade in a long for ten cubes.
tens
2
ones
13
33
- 18
Now we can subtract:
1. First the ones
2. Then the tens
tens
ones
Start with the ones.
52
- 37
Can we take 7 away from 2?
We need to regroup
tens
ones
52
- 37
Regroup 1 ten as 10 ones.
tens
4
ones
12
52
-37
Now we can subtract using
our new numbers!
Let's Practice !
tens
ones
69
- 7
Let's Practice !
tens
70 - 35
Remember:
If a problem is
written this way,
you want to
rewrite it to make
it easier to subtract.
ones
70
- 35
Let's Practice !
tens
ones
33
- 24
How will you know if
you have to regroup?
Here's a little poem to
help you remember:
COCOC
More on top?
No need to stop!
More on the floor?
Go next door!
-
25
12
-
Numbers the same?
Zeros the name!
-
81
61
74
36
Click on the picture below for more practice on
The National Library of Virtual Manipulatives Site
Change the
columns to
2 prior to
starting
102
85
- 37
48
Yes
No
103
94 - 25 = 71
Yes
No
104
67
- 58
105
88 - 34 =
106
42 - 7 =
107
34
- 26
Word Problems
with Regrouping
Click to return to
subtraction table
of contents
There are 65 students on the playground.
47 are wearing sneakers. How many are
not wearing sneakers?
What do we have to do
to find the answer?
tens
ones
65
- 47
Is there
"more on the floor?"
tens
5
ones
We can not take 7 away
from 5, so we have to
regroup 1 ten as 10 ones.
15
65
- 47
Now we can subtract:
First the ones
Then the tens
tens
5
ones
15
65
- 47
18
One day 45 cars and 19 trucks were washed
at the car wash. How many more cars than
trucks were washed?
What do we have to do
to find the answer?
tens
ones
45
- 19
How do I subtract?
There are 83 students eating lunch.
55 are eating hot lunch. How many
students are not eating hot lunch?
A soda cost 75 cents. Mr. West
has 46 cents. How many cents
does he need for a soda?
108 There are 50 students in the library. 27 of them
are wearing blue. How many are not wearing
blue?
A
33
B
37
C
23
D
77
109
Colin had 32 baseball cards. He sold 16. How
many were left?
110
Megan had 73 books at the yard sale. She sold
42. How many are left?
A
31
B
115
C
211
D
35
111 The pet store has 58 fish. They sell 39 fish. How
many fish are left at the pet store?
112
In art class, Jeff made 61 paper moons. Kelly
made 9. How many more moons did Jeff make?
Subtraction Practice
Click to return to
subtraction table
of contents
There are 84 apples on the
apple tree. Sara picks 68
apples. How many apples
are left on the tree?
How can we write
this problem to
find the difference?
Click each box to
check your answer
Do we have
YES! to regroup?
There
is do
more
the floor.
How
youon
know?
84
- 68
Regroup
1 ten
10 ones
What do
we for
do first?
Subtract
thedo
ones
first,
What
do we
next?
then the tens.
Susan draw 37 butterflies.
She colors 15 of them yellow.
How many butterflies does she have
left to color?
What do we have to
do to find the answer?
Click each box to
check your answer
Do we have
NO!to regroup?
Howisdo
youon
know?
There
more
top.
37
15
-
What
do we
first?
Subtract
thedo
ones.
Subtract
thenext?
tens.
What
do we do
Jenna picks up 34 sea shells.
She puts 17 of them in a box.
How many does she have left?
Sadie buys 74 pieces of paper.
She uses 44 for her book.
How many pieces of paper are left?
113
Mom bakes 23 cupcakes. She decorates 19
purple and the rest blue. How many were blue?
A
16
B
4
C
14
D
34
114 Becky buys 57 apples and oranges. 23 are
oranges. How many are apples?
A
80
B
24
C
34
D
23
115
Kira can jump a rope 94 times. Myah can jump a
rope 79 times. How many more times can Kira
jump than Myah?
116
The team scored 74 points. Shawn scored 36 of
the points. How many points did the rest of the
team score?
117
There are 49 markers in the box. 14 of them are
being used. How many are left in the box?
Mixed Practice
click to return to main
table of contents
There are 78 people wearing
hats and 35 people wearing red
hats. How many hats in all?
Is this anAddition
addition or
subtraction problem?
The do
question
asks
How
we know?
how many in all
WhatLine
do up
weour
have to
do tonumbers
find the
answer?
to add
78
+ 35
What do we add first?
78
+ 35
8+5=
Now what
do we do?
1
78
+ 35
3
Now what
do we do?
1+7+3=
1
78
+ 35
3
1
78
+ 35
113
The paint store has 64 cans of
paint. They sell 55 cans. How
many cans are left?
Is this an addition or
Subtraction
subtraction
problem?
The problem talks about taking
How
doasks
we know?
away
and
how many are
left.
Click each box
to check the
answer
Line up the numbers,
What do we have to
With the biggest number
do to find the answer?
On top to subtract.
64
- 55
0
What do we add first?
More on the floor,
go next door!
5 14
64
- 55
Now subtract:
ones first
then tens
There are 50 blue birds and 86 red birds.
How many birds are there all together?
What clue words tell us
what kind of problem
this is?
Two boys collected a total of 43
rocks. If John collected 22, how
many did Dave collect?
118
Kurt has 70 pennies. He gives Jay 48 pennies.
How many pennies does he have left?
A
38
B
22
C
118
D
32
119
Jenny does 29 jumping jacks. Nicole does 33
jumping jacks. How many jumping jacks did
they do all together?
A
52
B
16
C
62
D
4
120
There are 56 yellow flowers and 53 red flowers.
How many flowers in all?
121
38 kids have blue eyes and 27 kids have brown
eyes. How many more kids have blue eyes?
122 Jack has to drive 82 miles. He already drove 47
miles. How many more miles does Jack have to
drive?