00:00:00
10 – 8 =
- 2
15 – 6 =
- 9
20 – 12 =
- 8
50 – 30 =
- 20
2 X 5 =
- 10
2 X 2 =
- 4
3 X 4 =
- 12
2 X 8 =
- 16
2 X 7 =
- 14