Doubles facts to 20 +/-

Front

10 - 5

Back

5

Front

9 + 9

Back

18

Front

2 - 1

Back

1

Front

4 + 4

Back

8

Front

8 - 4

Back

4

Front

1 + 1

Back

2

Front

3 + 3

Back

6

Front

5 - 2

Back

3

Front

6 + 6

Back

12

Front

7 - 3

Back

4