计算7.5*2.3+2.9*2.5+12.5*0.4怎样算简便?
问题描述：
计算7.5*2.3+2.9*2.5+12.5*0.4怎样算简便?
答
=2.5x6.9+2.9x2.5+2.5x2
=2.5x（6.9+2.9+2)
=2.5x11.8
=2.5x2x5.9
=29.5