Missing Addends

Front

10 + ____ = 21

Back

11

Front

6 + ____ = 11

Back

5

Front

8 + ____ = 16

Back

8

Front

7 + ____ = 13

Back

6

Front

8 + ____ = 17

Back

9

Front

5 + ____ = 12

Back

7

Front

3 + ____ = 10

Back

7

Front

4 + ____ = 9

Back

5

Front

9 + ____ = 15

Back

6

Front

2 + ____ = 5

Back

3