1.25x(0.8+0.4)x2.5能用简便么?

来源：学生作业帮助网编辑：作业帮时间：2024/05/07 10:24:34

1.25x(0.8+0.4)x2.5能用简便么?
1.25x(0.8+0.4)x2.5能用简便么?

1.25x(0.8+0.4)x2.5能用简便么?
1.25x(0.8+0.4)x2.5
=1.25x2.5x0.8+1.25x2.5x0.4
=1x2.5+1.25x1
=2.5+1.25
=3.75

先算后式再算前式
(0.8*2.5+0.4*2.5)=3
3*1.25=3.75
答案是3.75

1.25x(0.8+0.4)x2.5
=1.25*0.8*2.5+1.25*0.4*2.5
=1*2.5+1*1.25
=3.75
是这样吗

可以简便计算：
1.25x（0.8+0.4）x2.5
=（1.25x0.8+1.25x0.4）x2.5
=（1+1.25x0.4）x2.5
=1x2.5+1.25x0.4x2.5
=2.5+1.25x1
=2.5+1.25
=3.75
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