Question

用简便方法计算下面各题．6.81+6.81×99  ...

用简便方法计算下面各题．6.81+6.81×99 0.25×185×40．

Answer 1

6.81+6.81×99
=（99+1）×6.81，
=100×6.81，
=681；

0.25×185×40
=0.25×4×10×185，
=1×10×185，
=1850．