5/9×7又5/12+1/9×1又7/12×5简便
问题描述：
5/9×7又5/12+1/9×1又7/12×5
简便
答
5/9×7又5/12+1/9×1又7/12×5
=5/9×7又5/12+5/9×1又7/12
=5/9×(7又5/12+1又7/12)
=5/9×9
=5
答
原式=5/9*7又5/12+5/9*1又7/12
=5/9*（7又5/12+1又7/12）
=5/9*9
=5
以后要会做哦