| 1) | 145 − 213 = | 2) | -622 − 117 = | 3) | -677 + 251 = |
| 4) | 751 + 728 = | 5) | -174 + 486 = | 6) | -598 + 278 = |
| 1) | 145 − 213 = -68 | 2) | -622 − 117 = -739 | 3) | -677 + 251 = -426 |
| 4) | 751 + 728 = 1479 | 5) | -174 + 486 = 312 | 6) | -598 + 278 = -320 |