In a group of ten coins there are either one or two fake coins and the rest are real. The fakes can be distinguished from the real coins only by weight. If there are two fake coins they will be equal weights.

Find a strategy to identify the fake coin or coins which uses only a balance scale no more than five times.

(In reply to wondering by Vernon Lewis)

The answer does cover both cases.

Posted by Marshall on 2007-07-20 06:59:09