Question

0.4✖️2.3✖️3.8的简便方法是什么？

Answer 1

0.4×2.3×3.8

＝0.92×3.8

＝0.92×（4一0.2）

＝0.92×4一0.92×0.2

＝3.68一0.184

＝3.496

Answer 2

解：0.4×2.3×3.8
=0.4x(2+0.3)×3.8
=(0.8+0.12)×3.8=0.92x3.8
=0.92(4-0.2)=3.68-0.184
=3.496

Answer 3

简算
0.4×2.3×3.8
=0.4×（2.5-0.2）×3.8
=（0.4×2.5-0.4×0.2）×3.8
=（1-0.08）×3.8
=3.8-0.08×3.8
=3.8-0.08×（4-0.2）
=3.8-0.32+0.016
=3.48+0.016
=3.496
简算时，首先考虑0.4的整数倍，用凑整法和乘法分配律运算。

Answer 4

=（（0.4*2）+（0.4*0.3））*3.8
=（0.8+0.12）*（3+0.8）
=0.92*3+（0.92*0.8）
=2.76+0.736
=3.496

Answer 5

0.4×2.3×3.8可以先将2.3变化一下
=0.4*(2.5-0.2)*3.8
=(0.4*2.5-0.4*0.2)*3.8
=(1-0.08)*3.8
=0.92*(4-0.2)
=0.92*4-0.92*0.2=3.496