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