1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+```````+(1/60+2/60+3/60+``````+59/60)=?
问题描述:
1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+```````+(1/60+2/60+3/60+``````+59/60)=?
答
=915