Adding on 1 to numbers

Front

9 + 1 = ?

Back

10

Front

7 + 1 = ?

Back

8

Front

5 + 1 = ?

Back

6

Front

8 + 1 = ?

Back

9

Front

1 + 1 = ?

Back

2

Front

5 + 1 = ?

Back

6

Front

2 + 1 = ?

Back

3

Front

10 + 1 = ?

Back

11

Front

3 + 1 = ?

Back

4

Front

4 + 1 = ?

Back

5