Change your Choice VS Don't Change (Monty Hall Dilemma)

Question

On the old American TV game show, "sale of the Century", the host would show the winning contestant 3 doors. Behind one, he explained, was a big prize. Behind the other two there was nothing. The contestant would choose one (say, door A). The Host would then open another (say, Door B), revealing nothing. He then would ask the contestant whether or not he or she wanted to choose again (A or C?) What should the contestant do?

Common Knowledge

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We know lots of common knowledge about the world. For example, we know the fact that planets around the sun had changed.

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But we don't know why someone exclude one planet from it. Like this we just know the fact but we don't try to understand the principle or reason that happen.

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Here is One Question

Try it!!!

If you are trapped inside the common knowledge you will not correct this question.

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Start!!!

There is 3 doors. A, B, C.
Inside one door there is huge gift for you. You can just chose one.

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When You choose one door. MC open another one door for you. And you figure there is nothing at the door you didn't choose.


Now there is only two door left.


At this situation MC ask you.

Are you going to change your chance
or are you going to stay at your choice.













People trapped inside their common knowledge says there is no difference changing the choice. They say probability is same at this two door. But is it true?!

First the answer is
Changing the Choice : 66%
Not Changing the Choice : 33%

Come out of your common knowledge and solve it again. You can probably find out MC will only choose empty door and this affect the probability of the choice.




This is famous question name 'Monty Hall Dilemma'. Lots of mathematicians also take wrong answer. This dilemma became famous that it was shown at the movie '21'.