Correction :
| 4 + 11 = 15 | 32 - 13 = 19 |
| 15 - 6 = 9 | 1 + 14 = 15 |
| 29 - 12 = 17 | 2 × 7 = 14 |
| 41 - 23 = 18 | 7 + 14 = 21 |
| 10 × 4 = 40 | 10 × 2 = 20 |
| 5 + 16 = 21 | 0 + 16 = 16 |
| 1 : 1 = 1 | 20 - 16 = 4 |
| 7 + 10 = 17 | 30 - 10 = 20 |
| 29 - 15 = 14 | 3 × 7 = 21 |
| 33 - 23 = 10 | 12 - 2 = 10 |