3.8*4.1-0.38 简算

问题描述:

3.8*4.1-0.38 简算

3.8*4.1-0.38
=3.8*4.1-3.8*0.1
=3.8*(4.1-0.1)
=3.8*4
=(4-0.2)*4
=4*4-0.2*4
=16-0.8
=15.2