Probability Riddle

Here's what doesn't make sense. You decide on a door to open. 1. Okay. Then 3 opens. Goat. You switch. 2/3 chance of car.

Now let's say we go back in time to the moment you picked 1 and picked 2 instead. 3 opens. Goat. You switch. Would it be 2/3 chance or 1/3 chance?? Surely you can't say that it would be 2/3. None of the items have moved since you went back in time.

I love it how no one cares what you say D3V. Flame inside the flame forum please. It is starting to annoy me.

Once again penny_bags, your imput in the fucking thread has nothing to do with it. Why do you keep flaming me? Did you notice how I said J/k, j/k, j/k, get it? JUST KIDDING, I made my point, and added a joke along with it. GET IT? HAR HAR!

How can you tell me that nobody cares what I say??? YOU OBVIOUSLY DO!! So do you know what that means??

YOUR A NOBODY

So how's about you keep your comment to yourself, and please, please, shut ....the.....fuck.....up

Here's what doesn't make sense. You decide on a door to open. 1. Okay. Then 3 opens. Goat. You switch. 2/3 chance of car. Now let's say we go back in time to the moment you picked 1 and picked 2 instead. 3 opens. Goat. You switch. Would it be 2/3 chance or 1/3 chance?? Surely you can't say that it would be 2/3. None of the items have moved since you went back in time.

How are you still possibly confused when Doofus's picture obviously explained it out so a 4 year old could even understand it?

Doofus's picture still makes no sense to me.

Anyway, given that fact that you'd rather go with the predictable choice of switching, if I were a gameshow host and you were the player, I'd just arrange it:

1: Car
2: Goat
3: Goat

It doesn't matter how you arrange it, or what door you are picking, the answer would always be to switch.

Doofus's picture graphically shows that every situation, no matter where the car is or what door you pick, that switching will always give you a 2/3 chance of winning opposed to the 1/3 you always get if you stay. This is very simple to see.

I understand what the picture says, and switching probably does raise your odds, but still, if you've got 2 doors, 1 with a car and 1 with a goat, there's a 50% chance you will get the car.

That's what is always initially thought, but that picture shows how, in probability terms, it actually isn't.

what??? so it ISN"T 50 percent chance??

That's right shorty.

I'm going to end the confusion here. This has gone on far too long.

The reason it's not 50% odds is because before you are shown which door is not the car, you pick one, thus eliminating it from the choice.

If one door were eliminated before you selected anything (i.e. selected from 3 instead of 2) then of the remaining two doors, there would be a 50% chance of selecting the car.

The thing that unevens the odds, however, is the fact that you removed one door from those allowed to be showed to you. The picture represents that identifying that in each case, 2/3rds of the time, the car can be obtained by switching doors.