Add It Up
3 + 3 = _____
3 + 3 = 6
8 - 4 = ____
8 - 4 = 4
9 = 7 + ____
9 = 7 + 2
3+1=2+___
3+1=2+2
Both sides must equal 4
10-2 = 4+___
10-2 = 4+4
You know 10-2=8.
What added to 4 will also equal 8?
4 + 5 = ____
4 + 5 = 9
Use the doubles + 1 strategy.
4 + 4 = 8, so 4 + 5 = 9
10 - 7 = _____
10 - 7 = 3
9 - ____ = 3
9 - 6 = 3
2+___=4+2
2+4=4+2
___-6 = 9-7
8-6 = 9-7
Both sides of the equal sign must be 2.
7 + 7 = _____
7 + 7 = 14
15 - 5 = ____
15 - 5 = 10
8 + ____ = 16
8 + 8 = 16
___+8=10+5
7+8=10+5
You know that 10+5=15
So think, 15-8=?
Or ? +8=15
0+13 = ___+8
0+13 = 5+8
4 + 7 = ____
4 + 7 = 11
Make a ten (7 + 3 = 10) add one more.
18 - 9 = ____
18 - 9 = 9
____ + 3 = 12
9 + 3 = 12
12+2=5+___
12+2=5+9
4+3+___=6+7
4+3+6=6+7
3 + 4 + 6 = _______
3 + 4 + 6 = 14
Make a 10 with 4 + 6 then add 3 more.
7 - 7 = ____
7 - 7 = 0
3+ __+ 7 = 14
3+4+4 = 14
___-6=9-5
10-6=9-5
You know that 9-5=4.
Make the other side of the equal sign the same amount!
12+2=20-___
12+2=20-6
12+2=14
20-___=14 OR
14+___-20