And lo On Wed, 17 Dec 2008 13:49:38 -0000, scott <sco### [at] scottcom> did  
spake thusly:

> If you have a box with N balls numbered 1 to N, and you repeatedly pull  
> one out at random (replacing it each time), on average how many times  
> would you expect to pull out a ball until you have seen all the balls 1  
> to N?

Do a search for Coupon Collector's Problem. For equal random drawings it's  
roughly nHn that is n * Sum k=1-n of 1/k multiplied by n

-- 
Phil Cook

--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com

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