The Monty Hall Problem
This problem is based on the game show, "Let's Make A Deal", which starred Monty Hall. There was much discussion of this problem in 1990 and 1991 in the column "Ask Marilyn" in Parade Magazine. Here is the problem:
Suppose that you are on a game show, and you're given the choice 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, open another door, say No. 3, which has a goat. He then says to you, "Do you want to switch and pick door #2?" Is it to your advantage to switch?
We will study this problem using probability.
Trial | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
Contestant
Chooses: |
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You Show Goat Under: | |||||||||||||||
Then Contestant
Chooses: |
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Did Contestant
Switch? |
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Did Contestant
Win or Lose? |
Total number of wins: _______ Total number of losses: ____________
Number of switch and win ____ Number of switch and lose __________
Number of stay and win ______ Number of stay and lose ____________
P(winning) = ________________ P(losing)=_________________________
P(winning | switch) = _______ P(winning | stay)= ________________
P(losing | switch) = ________ P(losing | stay)=__________________