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问题: (1-1/2加1/3-1/4加……加1/49-1/50)/(1/26加1/27加……1/50)

(1-1/2加1/3-1/4加……加1/49-1/50)/(1/26加1/27加……1/50)=?
一定有规律可循。

解答:

(1-1/2加1/3-1/4加……加1/49-1/50)/(1/26加1/27加……1/50)
=[(1/1+1/2+....+1/49+1/50)-(1/1+1/2+...+1/24+1/25)]/(1/26+1/27+…+1/50)
= 1
注: (1-1/2加1/3-1/4加……加1/49-1/50)
=[(1/1+1/2+....+1/49+1/50)-(1/2+1/4+...+1/48+1/50)] - (1/2+1/4+...+1/48+1/50)
= (1/1+1/2+....+1/49+1/50)-(1/1+1/2+...+1/24+1/25)