Question

0.64x1.25脱式计算能简算的要简算？

Answer 1

0.64x1.25
=0.8x0.8x1.25
=0.8x(0.8x1.25)
=0.8x1
=0.8

Answer 2

0.64x1.25
=0.08x8x1.25
=0.08x（8x1.25）
=0.08x10
=0.8
运用了乘法交换律和乘法结合律，做起来比较简便。

Answer 3

0.64x1.25
=0.8x(8x1.25)
=0.8x10
=8

Answer 4

0.64×1.25
=0.08×8×1.25
=0.08×（8×1.25）
=0.08×10
=0.8

Answer 5

原式=0.8×0.8×1.25
=0.8×1
=0.8.