一 道数学简便运算的题(81.3-81.38×0.9)÷0.25
问题描述:
一 道数学简便运算的题
(81.3-81.38×0.9)÷0.25
答
81.3×(1-0.9)÷0.25
答
[81.3-(81.3+0.8)×0.9]÷1/4
=[81.3-81.3×0.9+0.8×0.9]×4
=[81.3×(1-0.9)+0.72]×4
=(8.13+0.72)×4
剩下的自己算
答
原式=×4=(81.3-81.38+8.138)×4=8.058×4=(8.06-0.002)×4=32.24-0.008=32.232
答
(81.3-81.38×0.9)÷0.25
=81.38×(1-0.9)÷0.25
=81.38×0.1×4
=8.138×4
=32.552
答
=(81.38-81.38×0.9-0.08)*4
=(81.38*0.1-0.08)*4
=(8.138-0.08)*4
=8.058*4
=32.232