Question

3.87×7.9+38.7×0.21的简便运算？

Answer 1

算式可以转化为3.87*7.9+3.87*2.1＝3.87*（7.9+2.1）＝3.87*10=38.7

Answer 2

3.87×（7.9+2.1）=38.7

Answer 3

3.87X7.9+38.7X0.21
=38.7X0.79+38.7X0.21
=38.7X(0.79+0.21)
=38.7X1
=38.7