作业帮1/6+1/12+1/20+1/30+1/42
来源：学生作业帮助网 编辑：作业帮 时间：2024/11/15 23:55:17
1/6+1/12+1/20+1/30+1/42
1/6+1/12+1/20+1/30+1/42
1/6+1/12+1/20+1/30+1/42
1/6=1/2-1/3
1/12=1/3-1/4
1/20=1/4-1/5
1/30=1/5-1/6
1/42=1/6-1/7
1/6+1/12+1/20+1/30+1/42
=1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1/2-1/7
=5/14