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Eggalicious (Posted on 2002-07-05)

You have to boil a single egg for exactly nine minutes.

All you have are two hourglasses, able to measure (in sand) seven and four minutes, respectively.

How quickly, using only these two hourglasses, can you boil an egg?

See The Solution Submitted by qball

Rating: 2.7857 (14 votes)

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The correct solution (simple and elegant)

| Comment 18 of 20 |

(In reply to The correct solution by Keith Jones)

Or simply:

1 Start both timers

2.After 4 min, flip the smaller one; 3 minutes later the bigger one completes its turn; put the egg in water

3..Wait 1 minute for the smaller one to complete

4. Flip the smaller one twice

Posted by kowalski on 2004-08-08 20:54:49

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