Brain teaser: Which door to take?

C

Cordon - 2007

Oldie but a goodie!

You are in a room that only has two doors, Door A & Door B.
There are two guards in the room, Guard X & Guard Y.
One door leads to freedom and the other door leads to death.
You are trying to select the door that leads to freedom.
You can ask only one question and you must direct it to only one guard.
The only catch is that one guard is always truthful, the other guard will always lie, but you do not know which.

What is your question and which guard do you direct it to?
 
C

Craig H.

To the guard who always lies: "Don't get up, but would you please point out the door to freedom?"
 

Jim Wynne

Leader
Admin
Craig H. said:
To the guard who always lies: "Don't get up, but would you please point out the door to freedom?"
But one of the conditions is that you don't know which guard is which. So you know that A) there is a question that will get you the correct answer, and B) it doesn't make any difference which guard you ask. (I know the answer but I won't give it away this early.)
 
C

Cordon - 2007

Craig H. said:
To the guard who always lies: "Don't get up, but would you please point out the door to freedom?"

That's funny! :lmao: But no cigar,sorry.
 
S

SteelWoman

I found the answer by "googling" it, but I won't ruin it for you and paste it in here. Give ya' a hint, though - boolean
 
L

little__cee

Labyrinth?

Now I want to see this movie Labyrinth that is mentioned in all the Google hits - I've never even heard of it!
 
W

wilsonmm

If it's allowed, I'd ask either one, "Does the open door you're guarding lead to paradise?" The one that lies will have to agree the door is open since he lies, and his yes or no answer would be false. The one that tells the truth would have to correct your statement to say the door is closed, and his yes or no answer would also lead to the correct door.

Am I even warm?
 

Ron Rompen

Trusted Information Resource
Assume door A leads to freedom, and guard X stands by it. Guard X always tells the truth.

Ask either guard 'Which door would the other guard tell me leads to freedom?'

If you ask Guard X which door led to freedom, he would (truthfully) answer A. Guard Y would (falsely) answer B.

When you pose the question to Guard X, he will answer B (Guard Y lies)

When you pose the question to Guard Y, he will ALSO answer B (Guard X tells the truth, so Guard Y must like)

Whichever guard you question, and whichever door is indicated as the answer to the question, the OTHER door is the correct one to take.
 
D

D.Scott

Yes, but you may only ask one question and it must be directed to only one guard.

Dave
 
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