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Brendan
Posts:
3
Registered:
12/4/04


Solution!!
Posted:
Jan 27, 1999 7:15 PM


Dear Helena,
I read your problem and have solved it straight away! The key to the problem is being able to reduce the original number of coins to 3...for obvious reasons.
I must warn you...I'm only fourteen so I may not be able to answer what you really wanted.
However, I think one can determine the odd coin from 24 coins in four weighings.
Weighing 1 = determine heavier 12coins 2 = determine heavier 6coins 3 = determine heavier 3 coins 4 = determine heaviest coin
One cannot determine the odd coin from 38 in 4 weighings. This is because by the end of the third weighing one is left with four coins. In a single weighing one cannot find one heavier coin.
I hope you find this useful.
Brendan



