Invisible <voi### [at] devnull> wrote:
> If we select one ball, the probability of it being ball #1 is 1/N.

  You are thinking it in the wrong way.

  The very first time you select one ball, the probability it's a ball you
have never seen before is 1.

  The second time you select a ball, the probability it's a ball you have
never seen before is (N-1)/N.

  With the third ball, the probability is (N-2)/N. And so on.

-- 
                                                          - Warp

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