Question

怎样用简便方法计算54.9*0.38

Answer 1

1、第一种方法：

54.9×0.38

=55x0.38-0.1x0.38

=20.9-0.038

=20.862

2、第二种方法：

54.9X0.38

=(55-0.1)X(0.4-0.02)

=55X0.4-55X0.02-0.1X0.4+0.1X0.02

=22-1.1-0.04+0.002

=20.862

Answer 2

54.9*0.38
=54.9*0.4-54.9*0.02
=55*0.4-0.04-1.098
=22-1.138
=20.862