1/6+1/12+1/20+1/30+1/42

来源：学生作业帮助网编辑：六六作业网时间：2024/10/02 17:43:05

1/6+1/12+1/20+1/30+1/421/6+1/12+1/20+1/30+1/421/6+1/12+1/20+1/30+1/421/6=1/2-1/31/12=1/3-1/41/20=1/4

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