简便计算 1-1/6+1/42+1/56+1/72+1/90 = = = =

分类: 作业答案 • 2021-12-28 16:58:16

问题描述：

简便计算 1-1/6+1/42+1/56+1/72+1/90 = = = =
简便计算 1-1/6+1/42+1/56+1/72+1/90
=
=
=
=

答

1-1/6+1/42+1/56+1/72+1/90
=1-1/6+（1/6-1/7）+（1/7-1/8）+（1/8-1/9）+（1/9-1/10）
=1-1/6+1/6-1/7+1/7-1/8+1/8-1/9+1/9-1/10
=1-1/10
=9/10