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Topic: 12 billiard ball problem
Replies: 15   Last Post: Jan 4, 2013 12:07 PM

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 H. Peter Anvin Posts: 4 Registered: 12/12/04
Re: 12 billiard ball problem
Posted: Nov 18, 1997 6:53 PM

Followup to: <01bcf44e\$fef00320\$8de52ac2@jon>
By author: "Jonathan Pearce" <jvpearce@classic.msn.com>
In newsgroup: sci.math
>
> Does anybody know of an elegant solution to the twelve billiard ball
> problem?
>
> (Twelve apparently identical billiard balls, one of which is slightly
> heavier than the rest, determine which is the heavier one making only three
> weighings.)
>
> I would be very grateful for a reply.
>
> JVP.

Why make it so easy? Twelve billiard balls (gold bars, whatever...);
exactly one is *either* lighter *or* heavier than the others; find
which one it is *and* if it is lighter or heavier, in three
weighings by a balance scale.

My music teacher gave me this problem back in sixth grade. It's
solvable (and yes, I found the solution.)

-hpa
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Date Subject Author
11/18/97 Jonathan Pearce
11/18/97 Sam @ The NIMP Team
11/19/97 jhnieto@luz.ve
11/19/97 Sam @ The NIMP Team
11/18/97 Pat (Jedi In Training)
11/18/97 H. Peter Anvin
11/19/97 David Kastrup
11/19/97 jhnieto@luz.ve
3/3/99 bob vanderbrink
3/3/99 David Kastrup
11/20/97 Jeff Erickson
11/20/97 Brian Hutchings
1/7/98 Rosa Guia
11/10/98 James W.
10/27/03 Bill Bridges
1/4/13 Raymond C Phillips, LT USN Retired