Egg timers
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Revision as of 11:06, 20 May 2010 by Oscarlevin (talk | contribs)
Here is a variation on one of Richard Wiseman's Friday puzzles.
Puzzle
For dinner you decide to make a soft boiled ostrich egg. Problem is, an ostrich egg needs to boil for exactly seven minutes. After searching through your kitchen drawers, you find two hour-glass-style egg timers: one for three minutes, the other for five minutes. Is it possible to time exactly seven minutes using these timers? Is it possible to do so without any preparation?