Since the super bowl is coming up, here is a simple but enjoyable puzzle to give guests that may not be so enamored with the game. (Think wives)

All you need are toothpicks or matchsticks.

Arrange 16 sticks to look like the diagram below. There are 5 congruent(=) squares. The puzzle is to move (NOT REMOVE) 2 sticks to new locations so that there are only 4 congruent (=) squares. Each end of each stick must be connected to an end of another stick.

Ignore the dots.

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!_!
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...!_!

Here is an applet to play around with and other toothpick puzzles. http://mste.illinois.edu/users/mmcke...k/default.html and http://www.madras.fife.sch.uk/depart...rld/index.html

I did this trick in my Geometry classes, only I used magnetic sticks and steel balls. The kids loved playing with them and they are great for demonstrating a lot of geometric concepts, especially those dealing with 3-D

Steve