问题描述: 1/8+1/24+1/48+1/80+1/120的简便算法1/3+1/15+1/35+1/63+1/99+1/143 1个回答 分类:数学 2014-10-17 问题解答: 我来补答 1/8+1/24+1/48+1/80+1/120=1/4×(1/2+1/6+1/12+1/20+1/30) =1/4×(1/1*2+1/2*3+1/3*4+1/4*5+1/5*6) =1/4×(1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6) =1/4×(1-1/6) =1/4×5/6 =5/24 展开全文阅读