(2/9+1/6)÷7/2简便计算
问题描述:
(2/9+1/6)÷7/2简便计算
答
(2/9+1/6)×2/7
=2/9×2/7+1/6×2/7
=4/63+1/21
=4/63+3/63
=7/63