In the famous
"The Odd Coin" problem you are given twelve coins, exactly one of which is lighter or heavier than the other coins. You are to determine the counterfeit coin, and whether it is lighter or heavier than the other coins, in just three weighings with a balance.
Can you solve this problem with the additional restriction that you must decide what coins go on each pan for all three weighings before any weighing takes place?
(In reply to
re: Answer by Tristan)
Well, I can't take full credit. Years ago, when I first saw this problem, I read about this solution (in addition to the standard one). I had to think awhile (and scribble a lot) to re-derive it.
re(2): Answer
