四升五数学暑假专项:简便计算

四升五数学暑假专项:简便计算

  • 简介

    7.8-3.5+2.2-6.5 =7.8+2.2-(3.5+6.5) =10-10 =0 101×9.9 =(100+1)×9.9 =100×9.9+9.9 =990+9.9 =999.9 42-6.78-3.22 =42-(6.78+3.22) =42-10 =32 73.26-(18.9+3.26) =73.26-3.26-18.9

四升五数学暑假专项:简便计算