分类：教育/科学-学习帮助
问题：4/25*(1/1*5+1/5*9+1/9*13+1/13*17? 
简算
回答：4/25*(1/1*5+1/5*9+1/9*13+1/13*17+......+1/97*101 )
=4/25*{(1/4)*[(1-1/5)+(1/5-1/9)+(1/9-1/13)+...+(1/97+1/101)]}
=4/25*(1/4)*(1-1/5+1/5-1/9+1/9-1/13+...+1/97-1/101)
=4/25*(1/4)*(1-1/101)
=1/25*100/101
=4/101