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A Carpet With a Hole

One of the most likable stories I ever read to my little boy was Something from nothing by D. Blitz. In short it went like this:

When Yaakov was born, Grandpa Meir brought him a beautiful blanket. Yaakov liked the blanket very much. In time, the blanket grew worn out and needed fixing. Grandpa Meir had managed to make a pillowcase out of whatever remained of the blanket. Yaakov liked the pillowcase very much. When, after a few years, the pillow, too, became unusable, Grandpa Meir made out of the remainder a beautiful button. Yaakov warn proudly the button on his jacket until it went undone and got lost. This time, since Grandpa Meir could not create something from nothing, Yaakov sat down and wrote a story of the blanket's metamorphosis - apparently out of nothing. I remembered the story while working on the problem presented by the applet below.

A rectangular carpet with a hole is to be mended by slicing it into two pieces which then combine into a square carpet. The problem is pretty old and, in a description of a similar puzzle, [Frederickson, p. 66] mentions both S. Loyd and H. E. Dudeney.


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.


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Solution

References

  1. S. Blitz, My First Book of Jewish Stories, Mesorah Publications, Ltd., 1999
  2. G. N. Frederickson, Dissections: Plain & Fancy, Cambridge University Press, 1997

Copyright © 1996-2008 Alexander Bogomolny

 

 

 

 

 

 

 

 

 

 

 

 

 

 

To see the solution just hold the mouse down in the applet area and drag.


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

Several other dissection puzzles admit such a "stutter" solutions.

Equidecomposition by Dissection

  1. Carpet With a Hole
  2. Equidecomposition of a Rectangle and a Square
  3. Equidecomposition of Two Parallelograms
  4. Equidecomposition of Two Rectangles
  5. Equidecomposition of a Triangle and a Rectangle
  6. Equidecomposition of a Triangle and a Rectangle II
  7. Perigal's Proof of the Pythagorean Theorem
  8. Two Symmetric Triangles Are Directly Equidecomposable
  9. Wallace-Bolyai-Gerwien Theorem

Copyright © 1996-2008 Alexander Bogomolny

28680667Page copy protected against web site content infringement by Copyscape


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