24点题目：使用数字 4 4 6 9，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20个解（使用交换律变换后算一个解）,
难度系数是3星
★★★☆☆☆☆☆【
中等偏易24点题目
】。
| 序号 |
题目：4,4,6,9 |
| 1 |
(4 + 4) × (9 − 6) |
| 2 |
((4 × 4) × 9) ÷ 6 |
| 3 |
((9 × 4) × 4) ÷ 6 |
| 4 |
((9 × 4) ÷ 6) × 4 |
| 5 |
(4 × 4) × (9 ÷ 6) |
| 6 |
(9 × 4) ÷ (6 ÷ 4) |
| 7 |
(9 ÷ (6 ÷ 4)) × 4 |
| 8 |
(4 ÷ (6 ÷ 9)) × 4 |
| 9 |
(4 × 4) ÷ (6 ÷ 9) |
| 10 |
(9 × (4 ÷ 6)) × 4 |
| 11 |
(9 × 4) × (4 ÷ 6) |
| 12 |
(4 × (9 ÷ 6)) × 4 |
| 13 |
9 ÷ (6 ÷ (4 × 4)) |
| 14 |
4 ÷ (6 ÷ (9 × 4)) |
| 15 |
4 ÷ ((6 ÷ 9) ÷ 4) |
| 16 |
4 ÷ ((6 ÷ 4) ÷ 9) |
| 17 |
9 ÷ ((6 ÷ 4) ÷ 4) |
| 18 |
9 × (4 ÷ (6 ÷ 4)) |
| 19 |
9 × ((4 × 4) ÷ 6) |
| 20 |
9 × (4 × (4 ÷ 6)) |