1/12+1/20+1/30+.+1/9900
问题描述:
1/12+1/20+1/30+.+1/9900
答
1/12=1/3-1/4
1/20=1/4-1/5
所以原式=1/3-1/4+1/4-1/5+……+1/99-1/100
=1/3-1/100
=97/300