1.25×3.2×5怎样简便运算?

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/28 07:11:21

1.25×3.2×5怎样简便运算?
1.25×3.2×5怎样简便运算?

1.25×3.2×5怎样简便运算?
1.25×3.2×5
=1.25x8x0.4x5
=(1.25x8)x(0.4x5)
=10x2
=20

把3.2拆成4和8

1.25×3.2×5=1.25×8×0.4×5=10×2=20

1.25x4X0.8×5
=(1.25x4)X(0.8×5)
=5X4
=20