Three Holes Puzzle
Date: 05/02/2002 at 11:59:53 From: Ali Subject: Three Holes Puzzle A piece of plywood has three holes it it: a circular hole with a diameter of 2 cm, a square hole with 2 cm sides, and a triangular hole with a base and height of 2 cm. What object could both completely plug each hole AND pass completely through each hole? Please help me with this problem. Thanks. -Ali
Date: 05/03/2002 at 15:43:28 From: Doctor Ian Subject: Re: Three Holes Puzzle Hi Ali, Imagine starting with a board and cutting it so that the cross-section is 2 cm square: that is, the board would plug the square hole, and you could slide it all the way through. 2 cm +----+ 2cm / /| +----+ | | | | | | | | | | | | | | | Now turn this on its side, and lay it across the triangular hole. Cut away everything that doesn't fit through the hole, so you end up with something like this: plugs the square hole plugs the 2 cm this way triangular hole +----+ | this way 2cm / / | __ +----+ - v /| \ / | 2 cm / \/ | - You have one more direction from which to make it look like a circle. Can you take it from here? - Doctor Ian, The Math Forum http://mathforum.org/dr.math/
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