| 序号 | 题目:7,8,10,13 | |
|---|---|---|
| 1 | ((13 + 8) − 7) + 10 | |
| 2 | ((13 + 8) + 10) − 7 | |
| 3 | ((10 + 8) + 13) − 7 | |
| 4 | ((13 + 10) − 7) + 8 | |
| 5 | ((13 + 10) + 8) − 7 | |
| 6 | (10 + 8) + (13 − 7) | |
| 7 | (8 + (13 − 7)) + 10 | |
| 8 | (13 + (8 − 7)) + 10 | |
| 9 | (13 + (10 − 7)) + 8 | |
| 10 | (10 + (13 − 7)) + 8 | |
| 11 | (13 + 8) + (10 − 7) | |
| 12 | (13 + 10) + (8 − 7) | |
| 13 | 13 + (8 + (10 − 7)) | |
| 14 | 13 + (10 + (8 − 7)) | |
| 15 | 13 + ((10 + 8) − 7) | |