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Topic: The missing dollar problem
Replies: 3   Last Post: Mar 14, 1995 11:09 AM

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Angie S. Eshelman

Posts: 10
Registered: 12/6/04
Re: The missing dollar problem
Posted: Mar 13, 1995 8:41 PM
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I know exactly the problem you are talking about! However, it is *not*
*un*solvable... it is just that the "intuitive" method for solving this
problem is actually erroneous. It is somewhat like an "optical illusion"
for the mathematical part of one's brain. The problem goes something like

Three friends need a hotel room for the night. They are charged
$30 for the room, or $10 apiece. However, an hour later, the hotel manager
discovered that she overcharged the three for their room. She sends the
bellhop upstairs with $5 in change. On the way upstairs, the bellhop
decides to pocket $2 for himself (since no one will know), because it will
make the dividing of the change among the three guests much simpler. Once
upstairs, he returns $1 to each of the three men.
Since the three friends each paid $9 for the room ($10 originally
and $1 dollar in change) and the bellhop ended up with a $2 dollar
"tip"--for a total of $29 dollars--What happened to the other dollar of the
$30 that was originally paid?

Have fun!!

>I am looking for The Missing Dollar Problem. I have a group of kids that
>will find this one "interesting". I have searched high and low around this
>house, and the problem is no where to be found. I am hoping that someone on
>list will have it and post it.
>I am not sure exactly how it goes, but The Missing Dollar Problem is
>unsolvable. It starts out describing a man who is paying his hotel bill. He
>has $30 and the bill is $27. He tips the bellboy, and somehow gets some
>change. When it is all done, he is short a dollar.
>Does anyone have a copy of the problem?
>Thanks!!!!!! Diane McElwain

Angie S. Eshelman
116 Erickson Hall Office: (517) 353-0628
Michigan State University E-Mail:
East Lansing, MI 48824-1034

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