I recently came across a Monty Hall problem involving 5 doors. You are participating in a contest. There is one car behind five doors. After you select a door, the host will open three of the four remaining doors that do not contain the car. You are now left with two options. Do you stay with the original door or switch to the unopened door? And how would you explain your answer by drawing a probability tree for this scenario?

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    $\begingroup$ What have you tried? You can either pick the car or not. What is the chance of each? What happens in each case? $\endgroup$ Feb 17, 2019 at 2:43
  • $\begingroup$ Imagine the game is played many times. What happens if you always switch? Under what conditions do you win? What if you never switch? $\endgroup$
    – saulspatz
    Feb 17, 2019 at 17:04
  • $\begingroup$ What do you know about the Monty Hall problem in the standard telling? How does adding more doors change things? Suppose there were 100 doors? $\endgroup$
    – Doug M
    Jun 7, 2020 at 18:18


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