3.6 2.5+0.42 25+2×0.25简便计算十万火急!

分类: 作业答案 • 2022-06-09 17:23:30

问题描述：

3.6 2.5+0.42 25+2×0.25简便计算
十万火急!

答

是不是
3.6*2.5+0.42*25+2*0.25
=3.6*2.5+4.2*2.5+20*2.5
=（3.6+4.2+20）*2.5
=27.8*2.5
=(28-0.2)*2.5
=70-0.5
=69.5

答

=3.6*2.5+4.2*2.5+0.2*2.5
=（3.6+4.2+0.2）*2.5
=8*2.5
=20