4.9*0.7+18.32用【简便计算】
问题描述:
4.9*0.7+18.32用【简便计算】
答
原式:
4.9×0.7+18.32
=49×0.07+18.32
=(50-1)×0.07+18.32
=3.5-0.07+18.32
=21.82-0.07
=21.75
或
(5-0.1)×0.7+18.32
=3.5-0.07+18.32
=3.5+18.32-0.07
=21.82-0.07
=21.75