简便计算:[5/6-(5/12-2/5)]÷7/18

问题描述:

简便计算:[5/6-(5/12-2/5)]÷7/18

[5/6-(5/12-2/5)]÷7/18
=[5/6-5/12+2/5]*18/7
=[5/6+2/5]*18/7
=15/7+36/35
=111/35