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# Riddle me this...

You're on a game show and about to get the chance to win a brand new car. The game show host presents you with three doors, he tells you that behind one of the doors is the car and behind the other two doors there is a goat (so that's one car and two goats). You are told to pick one of doors where you think the car is behind, so you choose one of the doors but before you can get to open the door the host opens one of the other doors to reveal a goat (the host knows where the car is). Now the host gives you the option to either stick with your original choice or swap with what's behind the other unopened door. If you want the best chance to win the car which should you do?

A. Stay with your first choice.

B. Swap for the other door.

C. It doesn't matter.

A. Stay with your first choice.

B. Swap for the other door.

C. It doesn't matter.

Always Swap!

Banned

Once the host has opened a door, the car must be behind one of the two remaining doors. The player has no way to know which of these doors is the winning door, leading many people to assume that each door has an equal probability and to conclude that switching does not matter (Mueser and Granberg, 1999). This "equal probability" assumption, while being intuitively seductive, is incorrect. Under the conditions stated above, the player's chances of winning the car actually double by switching to the door the host offers.

The chance of initially choosing the car is one in three, which is the chance of winning the car by sticking with this choice. By contrast, the chance of initially choosing a door with a goat is two in three, and a player originally choosing a door with a goat wins by switching. In both cases the host must reveal a goat. In the 2/3 case where the player initially chooses a goat, the host must reveal the other goat making the only remaining door the one with the car.

The probability doesn't change.

At the start each door has 1/3 chance. When you pick a door, there is 2/3 probability that it will be behind one of the other two doors. When they open one of those doors and it's not there, then there is still 2/3 probability that it will be behind the other door, so you should always switch.

Banned

Earlier you had a 1 in 3 (33.3%) chance of getting the car.

Which means you had a 2 in 3 chance of a goat (66.6%)

So ok now theres two left but he had a 100% chance of picking right so logically you are much better off switiching, dont think Im explaining this well...

LOL :-D

Thats a nice simple explaination :thumbsup: Clever.

If when you picked the door first would you swap it for the two overs if the host let you, yes you would.

That is effectivley what you are doing

Like your style :-D

:giggle: at least you got your priorities straight!!!

My maths head is saying that it doesn't matter, the only problem is that the host knows which IMO is the only thing that can influence it.

Goats are more use than cars.

Goats keep the garden tidy, the kids amused and provides milk and at some point goat curry!

The only good use for the car is to go get some beer for the curry!:thumbsup:

'Now the host gives you the option to either stick with your original choice or swap with the other unopened door'

Wly would you swap a choice (to get a car) for and upopened door, sure get new ones in B&Q...

cant u get arrested for that lol, anyway i'm with the conspiracy theory, the host is tryin to either get u away from or help u get the car

on the other hand goats are a bit niffy, sniff the door!!

so in would choose the door further away from the original door containing the goat unless he opened the middle 1 lol

Original Poster

youtube.com/wat…lGg

lol remember you have to clean up the mess the goat leaves behind, also slaughtering the goat can be a messy task!! :-D

thanks...video clears it up.:thumbsup: