OK, here’s a pretty simple probability problem, but it took me a moment to think about… until my geniusness came up with the solution. The problem is:
You want to choose randomly between 3 choices, but all you have is one coin. What’s the minimum amount of times you need to flip the coin so that you can choose fairly between your 3 choices? (That is, so that each choice has a 33.3…% of being chosen?)
The first person to answer correctly gets the prize of being the first person to answer correctly.
(To complicate the problem, suppose you have two coins, but one has been tainted with iocane powder, and no immunities allowed…)