递等式巧算:1.125*63+36*125+125 2.4200*32/21

问题描述:

递等式巧算:1.125*63+36*125+125 2.4200*32/21

1.
125*63+36*125+125
=125*(63+36+1)
=125*100
=12500
2.4200*32/21
=(4200/21)*32
=200*32
=6400
完毕