1/5*8+1/8*11+……+1/98*101 简便方法
问题描述:
1/5*8+1/8*11+……+1/98*101 简便方法
答
1/5*8+1/8*11+……+1/98*101
=(1/3)*(1/5-1/8+1/8-1/11+...+1/98-1/101)
=1/3*(1/5-1/101)
=1/3*96/505
=32/505