The old game show, Let’s Make a Deal, featured a segment in which contestants could choose the prize behind one of three doors. “Behind one door is a car; behind the others, goats. You pick a door, say No. 1, and the host, who knows what’s behind the other doors, opens another door, say No. 3, which has a goat. He then says to you, ‘Do you want to pick door No. 2?’ Is it to your advantage to take the switch?”
This case provided an interesting case of conflict between our intuitive beliefs and math. This problem was so simple yet confusing, even math professors and other experts got it wrong. Below is an article about the whole story and below that is a link to play an online version of the game in which you can choose a door and then decide whether to switch. The site tallies your overall effectiveness at winning the prize.