In the movie 21, Professor Mickey Rosa poses an interesting puzzle to his class – The Monty Hall Problem.  Imagine you’re on a game show and the host presents to you three doors.  Behind two of the doors are goats.  Behind one of the doors is a car. Choose the correct door and you win the car.  Let’s say you choose Door #1.  The host, who knows what’s behind all the doors, opens  Door #3  and reveals a goat.  The host then offers you the choice of staying with Door #1  or switching to Door #2.   Should you switch doors at this point?  To answer this question you must first determine the probability of choosing the car and the probability of choosing a goat.

At first blush it may seem that it’s basically a coin flip.  After … Read More »