五年级数学寒假复习《小数简便计算》专项练习

五年级数学寒假复习《小数简便计算》专项练习


简介:
5.79×0.99 =5.79×(1-0.01) =5.79×1-5.79×0.01 =5.79-0.0579 =5.7321 1.01×0.86 =(1+0.01)×0.86 =1×0.86+0.01×0.86 =0.86+0.0086 =0.8686 86×2.8+15×2.8 =(86+15)×2.8 =101×2.8 =(100+1)×2.8 =100×2.8+1×2.8 =280+2.8 =282.8 19.8÷0.5-9.8×2 =19.8×2-9.8×2 =(19.8-9.8)×2 =10×2 =20 8.57÷5-3.57÷5 =(8.57-3.57)÷5 =5÷5 =1