2 6 9 9算24点
问题描述：
2 6 9 9算24点
两种算法
答
1:(9 - 6 + 9) × 2
2:((9 - 6) + 9) × 2
3:(9 - (6 - 9)) × 2
4:9 × (6 ÷ 9 + 2)
5:9 × ((6 ÷ 9) + 2)
6:9 × (2 + 6 ÷ 9)
7:9 × (2 + (6 ÷ 9))
8:(9 + 9 - 6) × 2
9:((9 + 9) - 6) × 2
10:(9 + (9 - 6)) × 2
11:(6 ÷ 9 + 2) × 9
12:((6 ÷ 9) + 2) × 9
13:2 × (9 - 6 + 9)
14:2 × ((9 - 6) + 9)
15:2 × (9 - (6 - 9))
16:2 × (9 + 9 - 6)
17:2 × ((9 + 9) - 6)
18:2 × (9 + (9 - 6))
19:(2 + 6 ÷ 9) × 9
20:(2 + (6 ÷ 9)) × 9