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Ponder This

August 2001

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Ponder This Challenge:

Puzzle for August 2001

This puzzle was sent in by Joel Ouaknine.

Suppose S is a finite set of points in the plane, such
that for any two points x,y in S, there is a third point
z in S, collinear with x and y (and different from x and y).
Show that all points of S are collinear.


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Challenge: 08/01/01 @9:00 AM EST
Solution: 09/06/01 @9:00 AM EST
List Updated: 09/06/01 @5:00 PM EST

People who answered correctly:

Amites Sarkar (08.01.2001 @ 11:07 AM EDT)

Henry Bottomley (08.01.2001 @ 12:56 PM EDT)
Ionel Santa (08.02.2001 @ 4:41 AM EDT)
Dharmashankar Subramanian (08.02.2001 @ 3:21 PM EDT)
Saibal Mitra (08.02.2001 @ 6:35 PM EDT)
Jayavel Sounderpandian (08.08.2001 @ 2:59 AM EDT)
Alexis Megas (08.08.2001 @ 12:24 PM EDT)
Reddy Nanchary (08.08.2001 @ 1:22 PM EDT)
Ross Millikan (08.08.2001 @ 2:52 PM EDT)
Samantha Levin (08.08.2001 @ 4:50 PM EDT)
Mukul Kumar (08.10.2001 @ 2:57 PM EDT)
L Shankar Ram (08.14.2001 @ 1:09 AM EDT)
Liuwei (08.20.2001 @ 3:13 AM EDT)
Victor Chang (08.20.2001 @ 1:15 PM EDT)
Ming Song (08.22.2001 @ 1:14 PM EDT)
George Ross (08.23.2001 @ 1:04 AM EDT)
Guangwu Xu (08.23.2001 @ 2:49 PM EDT)
Nancy Schwarzkopf (08.23.2001 @ 9:48 PM EDT)
David Fraser (08.28.2001 @ 5:39 AM EDT)
Dave Biggar (08.28.2001 @ 9:18 AM EDT)


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