1/1*2+1/2*3+1/3*4+1/4*5+.+1/99*100=谢谢了,
问题描述：
1/1*2+1/2*3+1/3*4+1/4*5+.+1/99*100=谢谢了,
答
1/1*2+1/2*3+1/3*4+1/4*5+.+1/99*100=(1-1/2)+(1/2-1/3)+(1/3-1/4)+(1/4-1/5)+...+(1/99-1/100)=1-1/100=99/100