简便计算:7.81减(3.81减1.65)+2.25
问题描述:
简便计算:7.81减(3.81减1.65)+2.25
答
7.81减(3.81减1.65)+2.25
=7.81 - 3.81 +1.65 +2.25
=4+ 3.9
=7.9