84*25 有几种简便运算方法

问题描述:

84*25 有几种简便运算方法

(100-4X4)X25
=2500-4X4X25
=2500-4X100
=2100
(80+4)X25
=80X25+4X25
=20X4X25+100
=2000+100
=2100
84*25
=84*25X4/4
=84/4X100
=21X100
=2100