简便计算6.8*3.4+15.9*3.2
问题描述：
简便计算6.8*3.4+15.9*3.2
答
6.8*3.4+15.9*3.2
=(10-3.2)*3.4+15.9*3.2
=10*3.4+(15.9-3.4)*3.2
=34+12.5*3.2
=74