Which Door

ahundiak

As a contestant on a game show, you are presented with three doors. Behind one door is 1 million dollars. Behind each of the other doors is a goat.

You pick a door. The host opens one of the two remaining doors and reveals a goat. You then have a choice between staying with your initial door or switching to the third door.

Do you:
A. Stay with your initial door
B. Switch to the other door.
C. Realize is does not matter if you switch or not.

mpirvul

Take the other door....you cannot go lower then a goat and you now have a 50/50 chance for the million. :p

Jedi_Legend

I would stay. I have been burned on too many multiple choice tests because I doubted my answer and changed it.

Elizabeth

I don't think it matters if you switch or not- you still have 2 unknown doors, and a 50/50 shot at your million either way.

I say go with the one with the coolest doorknob. 😃

-Elizabeth

Shadeless

first u have 33%, then when 1 door is revealed.

If u stay at the same door u still have 33% but when u switch, the 33% will switch to 50% since u now can choose out of the 2 doors.

Dun ask me why, i always disargued it, but in every damn test this question comes, the answer is switch.

NoFear

I'd ask the host which one he'd pick =)

rod_k

You switch. As mentioned before, you had a 33% chance of being right when you first guessed (meaning a 67% chance of being wrong). With one of the remaining doors eliminated you now have a 67% chance of being right when you switch (contrary to the 50% mentioned previously).

For a more easily followed example. I have a standard deck of cards (52, no jokers). Your job is to pick the Ace of Spaces. You pick your card, without looking. I then turn over one card at a time from the remaining cards showing you that it each is NOT the ace of spades. When I have one card left, I ask you if you want to switch. What do you think you should do? 😉

largo

I'd pick a goat over a million dollars any damn day and twice on sunday. Unless of course you put a sheep behind one of the other doors, then I may be tempted to try my luck again.

mpirvul

Somebody here is a very, very sick puppy. lol :p

ahundiak

Rod K got the correct answer. Congrats.

Largo,
Think about it. With a million dollars you could buy a whole herd of sheep.

largo

lol.

Darth Ahundiak comes through!

Okay, before daynah boots us both from this forum 🙂

Shadeless

yea lord k got it right, and i fully disagree with it.. always have done, i always say it's 50/50 after 1 door is gone 😃

but heck, gambling calculations never been my strongest point, i rather count..

😃

Elizabeth

Originally posted by Shadeless
yea lord k got it right, and i fully disagree with it.. always have done, i always say it's 50/50 after 1 door is gone 😃

I wholeheartedly agree Shadeless- it makes sense once you look at it from the "2 in 3" chance versus the "1 in 3" chance... but I also agree that it defies common sense that says regardless of how many doors there are to begin with, you still have a "1 in 2" shot of getting it right when it comes down to the end.

Hence why this "logic" thing always gets me LOL

I did manage to get an A in statistics though in college- go figure.

-Elizabeth

the_Igel

Does that man, who opens the door, know, that there's no money? If so, then 2/3. If not, then 1/2.
(Conditional probabilities: in one case the condition is "one of two doors doesn't lead to money", which is always true, and in other case it's "exactly this door doesn't lead to money", which is 1/2.)

rod_k

Does that man, who opens the door, know, that there's no money?

Yes, that's the premise, just as in the deck of cards example I gave, I would look at a card before turning it over.

the_Igel

And what will you do, if the card IS ace of spades? 🙂

rod_k

Oh, aren't you clever. I don't turn it over of course.