8.625*2.5+1.375*2.5-2.5*2简便运算

问题描述:

8.625*2.5+1.375*2.5-2.5*2简便运算

(8.625+1.375-2)*2.5=8*2.5=20

8.625*2.5+1.375*2.5-2.5*2
=2.5*(8.625+1.375-2)
=2.5*8
=20