Question

0.4✖️2.3✖️3.8的简便方法是什么？

Answer 1

可以这样算。
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
=3.8-0.304
=3.496

Answer 2

0.4×2.3×3.8
=4×0.23×3.8
=0.92×3.8
=3.8-0.08×3.8
=3.8-0.304
=3.496
这样算可以吗。

Answer 3

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 4

0.4*2.3*3.8
=0.92*3.8
=（4-0.2）*0.92
=4*0.92-0.2*0.92
=3.68-0.184
=3.496

Answer 5

0.4×2.3×3.8，
=2.3×0.4×(3＋0.8)，
=2.3×(1.2＋0.32)，
=2.3×1.52，
=1.52×(2＋0.3)，
=3.04＋0.456，
=3.496