Question

下面各题,你能用简便方法计算吗?1.0.76x9.9+0.076 2.11.72-（4.3x0.4+5.6） 3.12.

Answer 1

1.0.76x9.9+0.076

=0.076*99+0.076

=（99+1）*0.076

=100*0.076

=7.6

2.11.72-（4.3x0.4+5.6）

=10+1.72-1.72+5.6

=15.6

3.12.5x（8+0.8-0.047）

=12.5*8+12.5*0.8-12.5*0.04-12.5*0.007

=100+10-0.5-0.0875

=109.4125