24点题目：使用数字 3 6 9 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54个解（使用交换律变换后算一个解）,
难度系数是4星
★★★★☆☆☆☆【
中等难度24点题目
】。
| 序号 |
题目：3,6,9,12 |
| 1 |
((12 + 9) + 6) − 3 |
| 2 |
((9 + 6) + 12) − 3 |
| 3 |
((12 + 6) − 3) + 9 |
| 4 |
((12 + 6) + 9) − 3 |
| 5 |
((12 + 9) − 3) + 6 |
| 6 |
((12 − 3) + 6) + 9 |
| 7 |
(12 + 6) + (9 − 3) |
| 8 |
(9 + 6) + (12 − 3) |
| 9 |
(12 + (9 − 3)) + 6 |
| 10 |
(12 + (6 − 3)) + 9 |
| 11 |
(6 × (9 − 3)) − 12 |
| 12 |
(9 + (12 − 3)) + 6 |
| 13 |
(12 + 9) + (6 − 3) |
| 14 |
12 + (6 + (9 − 3)) |
| 15 |
12 + (9 + (6 − 3)) |
| 16 |
12 + ((9 + 6) − 3) |
| 17 |
((12 × 6) ÷ 9) × 3 |
| 18 |
((6 × 3) × 12) ÷ 9 |
| 19 |
((12 × 6) × 3) ÷ 9 |
| 20 |
((12 × 3) × 6) ÷ 9 |
| 21 |
(12 × (9 + 3)) ÷ 6 |
| 22 |
(12 × 6) ÷ (9 ÷ 3) |
| 23 |
(9 + 3) × (12 ÷ 6) |
| 24 |
6 × ((12 × 3) ÷ 9) |
| 25 |
12 × (6 ÷ (9 ÷ 3)) |
| 26 |
12 × ((6 × 3) ÷ 9) |
| 27 |
12 × ((9 + 3) ÷ 6) |
| 28 |
6 × (12 ÷ (9 ÷ 3)) |
| 29 |
(6 × 3) × (12 ÷ 9) |
| 30 |
(12 × (6 ÷ 9)) × 3 |
| 31 |
(12 × 6) × (3 ÷ 9) |
| 32 |
(6 ÷ (9 ÷ 12)) × 3 |
| 33 |
(6 × 3) ÷ (9 ÷ 12) |
| 34 |
(12 × 3) × (6 ÷ 9) |
| 35 |
(9 + 3) ÷ (6 ÷ 12) |
| 36 |
(12 × 3) ÷ (9 ÷ 6) |
| 37 |
(6 × (12 ÷ 9)) × 3 |
| 38 |
(12 ÷ (9 ÷ 6)) × 3 |
| 39 |
6 ÷ ((9 ÷ 3) ÷ 12) |
| 40 |
12 × (3 × (6 ÷ 9)) |
| 41 |
3 ÷ (9 ÷ (12 × 6)) |
| 42 |
12 ÷ ((9 ÷ 6) ÷ 3) |
| 43 |
6 ÷ ((9 ÷ 12) ÷ 3) |
| 44 |
12 ÷ (9 ÷ (6 × 3)) |
| 45 |
12 × (6 × (3 ÷ 9)) |
| 46 |
6 ÷ (9 ÷ (12 × 3)) |
| 47 |
6 × (3 ÷ (9 ÷ 12)) |
| 48 |
12 ÷ (6 ÷ (9 + 3)) |
| 49 |
3 ÷ ((9 ÷ 12) ÷ 6) |
| 50 |
6 × (3 × (12 ÷ 9)) |
| 51 |
6 × (12 × (3 ÷ 9)) |
| 52 |
12 ÷ ((9 ÷ 3) ÷ 6) |
| 53 |
12 × (3 ÷ (9 ÷ 6)) |
| 54 |
3 ÷ ((9 ÷ 6) ÷ 12) |