# Probability: Two Goats And A Car behind three gate, how to locate the car?

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You are on a game show and there are three doors. The presenter tells you that behind one of doors there is a car and behind the other two are goats. If you pick the car you win it. After you have picked a door the presenter opens a different door with a goat behind it, he then gives you the chance to change what door you open. What should you do?

Hint: It is not 1/2 as you would first think.

posted Jan 28, 2014

This is a classic Problem aka Monty Hall Problem. If anyone has seen the kevin spacey movie 21 you will know the answer.

Your chosen door has 1/3 chance of getting you a car. The exposed goat door has a 0/3 chance of getting you a car. The third door thus has a 2/3 chance of getting you a car.

You should swap.

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