1/1*2+1/2+3+1/3*4+1/4*5+……+1/199*200

问题描述:

1/1*2+1/2+3+1/3*4+1/4*5+……+1/199*200

=1-1/2+1/2-1/3+1/3-1/4+……+1/199-1/200
=1-1/200
=199/200