1. 1 + 19 = 19 4 5 20
2. 10 + 8 = 26 18 28 21
3. 20 - 7 = 34 1 35 13
4. 5 - 13 = 24 31 -8 12
5. 1 - 19 = 22 -18 9 33
6. 2 - 17 = -15 8 4 2
7. 15 - 18 = -3 15 32 40
8. 4 + 8 = 23 39 34 12
9. 2 - 7 = -5 12 5 38
10. 12 + 20 = 4 2 25 32