http://mathforum.org/library/drmath/view/57965.html

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Date: 04/09/98 at 11:35:24
From: Doctor Rothman
Subject: Re: Where's the 30th dollar?

Hi. The first time I read it, I didn't get it either. But then I
realized that you just have to be REALLY careful about how you count
the dollars.

Let's give each of the $30 a number from 1-30, keep track of each
individual dollar, and see how the problem works.

Dollars numbered 1-30 are given to the manager. Then he wants to give
$5 back, so he keeps the dollars numbered 1-25, and gives numbers
26-30 to the bellboy in the form of a five dollar bill. The bellboy
splits up the five to get 5 one's: numbers 26, 27, 28, 29 and 30.
He gives numbers 26, 27 and 28 to the customers and keeps numbers 29
and 30 for himself.

-Doctor Rothman, The Math Forum
Check out our web site! http://mathforum.org/dr.math/
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we win