问题描述: 5/6-7/12+9/20-11/30+13/42怎么简算? 1个回答 分类:数学 2014-11-10 问题解答: 我来补答 5/6-7/12+9/20-11/30+13/42=1/2+1/3-(1/3+1/4)+1/4+1/5-(1/5+1/6)+1/6+1/7=1/2+1/3-1/3-1/4+1/4+1/5-1/5-1/6+1/6+1/7=1/2+1/7=9/14 展开全文阅读