1/2+1/3+1/4+1/6+1/12+1/48+1/56
问题描述:
1/2+1/3+1/4+1/6+1/12+1/48+1/56
答
1/2(24/48)+1/3(16/48)+1/4(12/48)+1/6(8/48)+1/12(4/48)+1/48+1/56
=72/48(3/2=84/56)+1/56=85/56