80.5*2.8+143.5

分类: 作业答案 • 2022-01-15 23:48:07

问题描述：

80.5*2.8+143.5

答

=80.5*（3-0.2）+143.5
=80.5*3-80.5*0.2+143.5
=241.5-16.1+143.5
=143.5-16.1+241.5
=127.4+241.5
= 368.9