1.5.8.9四个数加减乘除要等于24

(9-5-1)*8=24;

8*[9-(5+1)]=24, 9/1-5/8=9/3/8=3*8=24

[9-5-1]*8

24点这东西不必要动那么多脑子的。
http://www.***.com/tool/24.htm
电脑会帮你算。
你提的问题答案是
1: (1 - 9) × (5 - 8)
2: (5 - 8) × (1 - 9)
3: (8 - 5) × (9 - 1)
4: 8 × (9 - (1 + 5))
5: 8 × (9 - ...

（9-5-1）*8=24

1, 5, 8, 9的24点答案：



1: (1 - 9) × (5 - 8) =24

2: (5 - 8) × (1 - 9)
=24

3: (8 - 5) × (9 - 1)
=24

4: 8 × (9 - (1 + 5))
=24

5: ...