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Math Help - The Monty Hall Paradox

  1. #1
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    The Monty Hall Paradox

    For anyone who hasnít heard of this paradox, try to figure this one out. Iím sure youíll be very satisfied if you manage to for yourself:

    There are 3 identical boxes. Inside 1 of those 3 is a prize. You are asked to pick 1, after which 1 of the remaining empty boxes is taken away. Being left with 2 (1 with the prize, 1 without), you are then asked if you would like to change your mind from the box you chose originally to the other box that is left. You are then shown whether or not the box you have finally decided on has the prize and are given it if it does.

    The question is:
    Does it matter whether or not you change your mind when asked if you would like to and why?
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  2. #2
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    Yes it does matter if you change your mind, If your swap your more likely to win!

    but you may ask why?


    well lets go through the game as the host.
    You start playing and you pick your frist box, On your first go the chances of you picking a box without the prize is 2/3
    Now lets look at the two left. 2 thrids of the time the host will not have a choice of what boxhe/she may take away! because there are only two to choose from and one is the prize so it may not be taken away.

    so you can dedue that the 2 thrids of the time the box taken away is the only box the host could take away. meaning it would be a good idea to swap unless of course you pick the correct box the first time round (but there is only a 1/3 chance of that happening)
    Last edited by bobak; December 27th 2007 at 02:45 PM.
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  3. #3
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    This is a dead horse, beaten to death many, many times over.
    Monty Hall Problem
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  4. #4
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    What is so hard about Monty Hall? When I first heard it many years ago I found it trivial. The thing that really supprises me about this problem is why people just cannot understand it, it really is simple. And the majority of the world believes that it makes no difference .

    Since it has been mentioned many times before, and you can find it on the internet. I am going to close this thread because this is going to turn into one of those pseudomath threads.

    Just consider this. There are 100 doors. You pick 1. The other 98 are opened to be empty. Now just 2 remain. Will you still say that it makes no difference?!?! Clearly saying it is 50-50 is a wrong argument.
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