45+4.5+0.45+0.045的简便计算

问题描述:

45+4.5+0.45+0.045的简便计算

45+4.5+0.45+0.045
=45×(1+0.1+0.01+0.001)
=45×1.111
=5×9.999
=5×10-5×0.001
=50-0.005
=49.995