A riddle I can't figure out.

[Legolas]

One more thing, in this 'riddle' it does not matter if you pick door x first and door y later, or door y and then y, or door z and then x, or ...
It's only the result that counts.

You face two doors, one is right, one is wrong. What is the chance of picking the right one?


That's not to say you are right about there being several ways to reach the same effect. The chances of doing it in a particualr way are less than 50, less than 33%. But that's not the issue


Before I forget, the other riddle's answer was an onion

[Barry the Sprout]

That logic doesn't work Legolas as there aren't two doors there are three. Remember that when the quizmaster opens one he doesn't open one at random - he opens one without a prize. That is very significant as if you haven't picked the right one (i.e. 66% of the time) then he only has one door he can open. The fact that when he asks you if you want to change there are only two doors is completely irrelevant.

But we are going round in circles on this one. The maths community of the world is actually on my side. So there!!!

[Talthyr Malkaviel]

No-ones answered my puzzle yet, and no, there was no third person involved (or 4th etc), and they didn't kill each other, they din't die from being hit by anything or hitting anything, they didn't die from natural causes.
What did cause them to die?

[Barry the Sprout]

They were repeatedly confronted by a really hard riddle that they couldn't solve. As such their brains stopped working out of protest.

Seriously? I have no idea I am afraid.

[Talthyr Malkaviel]

Right, I'm just gonna repost this, but modified so everyone can try it.

quote:

---

Originally posted by Talthyr Malkaviel:
I've got one. (It's lateral thinking)

Anthony and Cleopatra are lying dead on the floor.
Near them is a table, which has been skewed slightly, a bowl lies smashed on the floor, and there is a puddle of water on the floor.
They did not drown and they did not kill each other, they didn't die of natural causes (e.g old age), there was no third person to kill them, and they didn't die from the actions of any other person, including themselves, or for example being hit by something, or hitting themselves with something.
What caused them to die?

---

[Dresdan]

D**n, and I was just getting over the headache Legolas, and 250 gave me the other night. I knew I shouldn't have stopped in here.

[LennonCook]

on the doors one..
The results are muttually exclusive, meaning that the door you pick in the first instance does NOT affect the second choice.
And we know that the quiz master picks a losing door- this is significant. if u have the right door to start with the choice is random. if u have a wrong dor the other wrong /*door opens. so no matter what happens ur left with a right door and a wrong door. This means the results are mutually exclusive. You therefore have a 50% chance of picking the right door.

[LennonCook]

Lets assume the door which opens is Random...

3 doors- D1 D2 D3
D1 has the prize. You choose D2.
Now if the choice was random we must assume in turn that each door opens.
If D1 opens- You know which door did have the prize, but you didnt pick it. 0% Chance.
If D2 Opens- You must choose between D1 and d3- You know one has a prize and the other doesnt. 50% chance.
If D3 Opens- Same as D2.
NOw lets assume You Pick D1.
D1 Opens-You got it Right!!! Screw Probability!!
D2 or D3 Opens- See above.
NOte that the white writing assumes the opened door is random, the blue in my previous post assumes it is not.

[Legolas]

Talthyr, I don't think anyone here'll ever figure it out.

[Sir Kenyth]

The difference, you silly folk, is in whether or not you get to see what's behind a door before making another choice. If you make all the choices before opening any of the doors, the spread is equal. Once a door is opened, it's variable is known and the spread is now distributed over the remaining doors.