1/2+1/6+1/12+1/20+1/30=?

1/2+1/6+1/12+1/20+1/30=?
1/2+1/6+1/12+1/20+1/30=?

1/2+1/6+1/12+1/20+1/30=?

1/2+1/6+1/12+1/20+1/30
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6
=1-1/6
=5/6
如果满意记得采纳哦！你的好评是我前进的动力。(*^__^*) 嘻嘻……

原式=30/60+10/60+5/60+3/60+2/60=5/6

1/（1✘2）+1/（2✘3）+1/（3✘4）+1/（4✘5）+1/（5✘6）=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6=1-1/6=5/6