You are presented with 9 coins from an archeological dig near the highlands of
Tibet. One of them contains a precious
jewel that can make you extremely wealthy.
The coin with the jewel is slightly heavier
than the others, the other eight are
identical. You can only choose once so you
are given 2 scales so that you can weigh the
coins. Here’s the dilemma, each balance
scale can only be weighed once. Is it
possible to select the slightly heavier coin
containing the jewel using each of the two
scales only once? Explain why or why not.