The Student Room Group

Can YOU figure this out ?

So there are 3 doors. Behind 2 of the doors there's nothing but behind 1 there is a nice shiny lambo :smile: . Now you have to pick a door. After you do that The presenter ones one of the doors and shows a door that is empty. Now you are left with 2 doors. One you chosen and one other that is left. The presenter gives you a chance to either switch door or stick with your one. What do you do ? Which gives a higher chance of winning ?

:frown: Sorry revision is boring
Switching. It's the Monty Hall problem. Do you want an explanation?
Original post by looktoyourright
So there are 3 doors. Behind 2 of the doors there's nothing but behind 1 there is a nice shiny lambo :smile: . Now you have to pick a door. After you do that The presenter ones one of the doors and shows a door that is empty. Now you are left with 2 doors. One you chosen and one other that is left. The presenter gives you a chance to either switch door or stick with your one. What do you do ? Which gives a higher chance of winning ?

:frown: Sorry revision is boring


I would change
Original post by donutellme
Switching. It's the Monty Hall problem. Do you want an explanation?


Yes! :smile:
#MontyHall
Reply 5
Original post by JulieWaters
Yes! :smile:


When you first choose your door, there are 2 empty doors and 1 door with the prize in it. Thus, the chances of you having chosen the correct door is 1/3. Now that one of the empty doors has been removed, there is only 1 door with the prize in it and 1 empty door. The chances of you having chosen the prize is still 1/3, which means the chances you picked an empty door are 2/3. Since you get to switch doors, if the chances you picked an empty door are 2/3 then when you switch you have a 2/3 chance of winning the prize, compared to a 1/3 chance if you stay with the original door.

Hope this helps!
Original post by JulieWaters
Yes! :smile:


3 doors in total. 2 are empty. This gives a 2/3 chance of picking an empty door.

So you're more likely to pick an empty door than the car.

Now, once they open the empty door, the other door is either empty or Lamborghini.

Since you're more likely to pick an empty door, if you switch, then you'll get Lambo.

On the other hand, 1/3 chance of getting Lambo.
Original post by tomtjl
When you first choose your door, there are 2 empty doors and 1 door with the prize in it. Thus, the chances of you having chosen the correct door is 1/3. Now that one of the empty doors has been removed, there is only 1 door with the prize in it and 1 empty door. The chances of you having chosen the prize is still 1/3, which means the chances you picked an empty door are 2/3. Since you get to switch doors, if the chances you picked an empty door are 2/3 then when you switch you have a 2/3 chance of winning the prize, compared to a 1/3 chance if you stay with the original door.

Hope this helps!


Yeah nice - not going to lie revision is boring and that problem was always interesting . Always got people puzzled
Monty Hall.

You should switch.

Humans don't understand this but pigeons do.
Original post by leavingthecity
Monty Hall.

You should switch.

Humans don't understand this but pigeons do.


you a pigeon or something
Original post by donutellme
you a pigeon or something


I wish!

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