1又1/3+7/12-9/20+11/30-13/42=多少?

分类: 作业答案 • 2021-12-23 10:30:29

问题描述：

答

=4/3+(1/3+1/4)-(1/4+1/5)+(1/5+1/6)-(1/6+1/7)
=4/3+1/3+1/4-1/4-1/5+1/5+1/6-1/6-1/7
=5/3-1/7
=32/21
=1又21分11