17/24×1/5+7/24÷5+15

问题描述:

17/24×1/5+7/24÷5+15

17/24×1/5+7/24÷5+15
=17/24×1/5+7/24×1/5+15
=(17/24+7/17)×1/5+15
=1/5+15
=15又1/5