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