24点题目：使用数字 1 5 7 12，利用加减乘除、括号算出24。数字顺序可以任意调换，下面列出所有可行算式。
本题共有48个解（使用交换律变换后算一个解）,
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中等偏易24点题目
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| 序号 |
题目：1,5,7,12 |
| 1 |
((7 × 5) + 1) − 12 |
| 2 |
((12 + 5) + 7) × 1 |
| 3 |
((12 + 7) × 1) + 5 |
| 4 |
((12 × 1) + 5) + 7 |
| 5 |
((12 × 1) + 7) + 5 |
| 6 |
((7 × 5) − 12) + 1 |
| 7 |
((12 + 7) + 5) × 1 |
| 8 |
((12 + 5) × 1) + 7 |
| 9 |
(7 + 5) + (12 × 1) |
| 10 |
(12 + (5 × 1)) + 7 |
| 11 |
(12 × 1) × (7 − 5) |
| 12 |
(12 × 1) + (7 + 5) |
| 13 |
(5 × (12 − 7)) − 1 |
| 14 |
(12 + 5) + (7 × 1) |
| 15 |
(12 × (7 − 5)) × 1 |
| 16 |
(12 + 7) + (5 × 1) |
| 17 |
(12 + (7 + 5)) × 1 |
| 18 |
(12 + (7 × 1)) + 5 |
| 19 |
(7 × 5) − (12 − 1) |
| 20 |
12 × ((7 − 5) × 1) |
| 21 |
12 + (7 + (5 × 1)) |
| 22 |
12 + ((7 × 1) + 5) |
| 23 |
12 + ((7 + 5) × 1) |
| 24 |
12 × ((7 × 1) − 5) |
| 25 |
12 × (7 − (5 × 1)) |
| 26 |
((12 + 7) ÷ 1) + 5 |
| 27 |
((12 ÷ 1) + 5) + 7 |
| 28 |
((12 + 5) ÷ 1) + 7 |
| 29 |
((12 + 7) + 5) ÷ 1 |
| 30 |
((12 + 5) + 7) ÷ 1 |
| 31 |
((12 ÷ 1) + 7) + 5 |
| 32 |
(12 ÷ 1) + (7 + 5) |
| 33 |
(12 + (5 ÷ 1)) + 7 |
| 34 |
(12 ÷ 1) × (7 − 5) |
| 35 |
(12 + (7 + 5)) ÷ 1 |
| 36 |
(7 + 5) + (12 ÷ 1) |
| 37 |
(12 × (7 − 5)) ÷ 1 |
| 38 |
(12 + 7) + (5 ÷ 1) |
| 39 |
(12 + 5) + (7 ÷ 1) |
| 40 |
(12 + (7 ÷ 1)) + 5 |
| 41 |
12 × ((7 ÷ 1) − 5) |
| 42 |
12 + (7 + (5 ÷ 1)) |
| 43 |
12 × (7 − (5 ÷ 1)) |
| 44 |
12 + ((7 + 5) ÷ 1) |
| 45 |
12 × ((7 − 5) ÷ 1) |
| 46 |
12 + ((7 ÷ 1) + 5) |
| 47 |
(7 − 5) ÷ (1 ÷ 12) |
| 48 |
12 ÷ (1 ÷ (7 − 5)) |