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John Sharp's Paradox:
How Is It Possible?

The applet below illustrates a dissection akin to the ones of Curry, Hooper, Langman and Sam Loyd Son. John Sharp mentions it with a reference to his notes in an enlightening article, but demurs as to the source. Originally, a 13×13 square is cut into three pieces which, after a rearrangement appear to combine into an 8×21 rectangle - a loss of one square.

The puzzle is easily modified by changing the dimensions according to the properties of the Fibonacci sequence. Upon rearrangement of the pieces, a single square seems to intermittently appear or disappear.


This applet requires Sun's Java VM 2 which your browser may perceive as a popup. Which it is not. If you want to see the applet work, visit Sun's website at http://www.java.com/en/download/index.jsp, download and install Java VM and enjoy the applet.


Buy this applet

(The three pieces can be dragged from the square to the rectangle and backwards.)

References

  1. J. Sharp, Fraudulent dissection puzzles - a tour of the mathematics of bamboozlement, Mathematics in School, The Mathematical Association, September, 2002

Dissection Paradoxes

Copyright © 1996-2008 Alexander Bogomolny

28725821Page copy protected against web site content infringement by Copyscape


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