求简便算法(75+240)*(20-5)== =脱式计算
问题描述:
求简便算法
(75+240)*(20-5)
=
=
=
脱式计算
答
(75+240)*(20-5)
=(15+300)*15
=15*15+300*15
=4725
答
(75-5)*(20+240)
=70*260
=1820