Question

4×5+12×5的简便计算

那位老师可以回答一下，谢谢啦

Answer 1

解：

原式

=(4+12)x5  乘法分配律

=16x5

=80

Answer 2

12.5×0.25×3.2
=12.5×0.25×4×0.8
=(12.5×0.8)×(0.25×4)
=10×1
=10

12.5×4.5+4.5×12.5+12.5
=12.5×(4.5+4.5+1)
=12.5×10
=125