Remove Five Toothpicks, Leave Three Squares
Date: 09/16/2002 at 20:49:27 From: Cassie Bass Subject: Math Puzzle If you have six squares made up of toothpicks, how can you remove five toothpicks and leave three squares?
Date: 09/16/2002 at 23:31:37 From: Doctor Peterson Subject: Re: Math Puzzle Hi, Cassie. You didn't say how many toothpicks you have or how they are arranged, but I'll suppose they are like this: _ _ _ |_|_|_| |_|_|_| This uses 17 toothpicks. When you remove 5, you'll have 12 of them to make 3 squares. That means you'll have 4 per square, so each toothpick has to be in exactly one of the squares, rather than seven of them being shared by two adjacent squares as in the original layout. How could those three squares be arranged so they don't share any edges? Which toothpicks do you have to remove to do that? - Doctor Peterson, The Math Forum http://mathforum.org/dr.math/
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