0.8x0.25x0.4x12.5的简便方法

1、将12.5和0.25交换个位置

  0.8x0.25x0.4x12.5

=0.8x12.5x0.4x0.25

2、8x0.25算出为10

   0.8x12.5x0.4x0.25

=10x0.4x0.25

3、将0.25和10交换个位置

  10x0.4x0.25

=0.25x0.4x10

4、25x0.4算出为0.1

   0.25x0.4x10

=0.1x10

5、经过运算，最后结果为1

6、运算全过程为：

   0.8x0.25x0.4x12.5

=0.8x12.5x0.4x0.25

=10x0.4x0.25

=0.25x0.4x10

=0.1x10

=1