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A classic American sixties game show, hosted by Monty Hall, involved contestants choosing one of three doors. Behind one of the doors was a valuable prize such as a new car. Behind the other two doors was something relatively worthless like a banana. After the contestant chooses one of the three doors Monty Hall (who knows which door has the prize behind it) always reveals a door (other than the one chosen) that has a worthless item behind it. He now poses the question to the contestant:

"*Do you want to switch doors
or stick to your orginal choice*?"

Most people assume that there is no benefit in switching, i.e. that by sticking to their orginal choice they have a 50% chance of winning.

Click here for an explanation of why they are wrong.

Norman Fenton

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