5,5,5,1作用四则运算等于24

问题描述:

5,5,5,1作用四则运算等于24

1:5 × (5 - 1 ÷ 5)
2:5 × (5 - (1 ÷ 5))
3:(5 - 1 ÷ 5) × 5
4:(5 - (1 ÷ 5)) × 5