Logic question

[JohnCU]

A missionary lost in Southern California stops at a fork in the road. He knows that two motorcycle gangs inhabit the area, one of which always tells the truth and one of which always lies. He wants to know which road leads to Disneyland. What one question should he ask?

 

[SnipeMasterJ13]

Doesn't matter, either way he will have an answer.

My bad, read it too fast. Hmmm, which question to ask?....I would go with..."Sup bitches, which way to disneyland?"

 

[shortylickens]

I think the correct answer is ask them both what the other would say to the question of 'Wheres Disneyland?'
But I think that answer always assumes the liars wont just say 'I dont know' or that each faction knows of the others tendancies.


In reality he should head home. Just because they alwasys tell the truth, doesnt mean they wont rape his punk ass.

 

[chrisms]

Originally posted by: shortylickens
I think the correct answer is ask them both what the other would say to the question of 'Wheres Disneyland?'

 

[Jzero]

"I'm Alph and he's Ralph..."

 

[jagec]

Originally posted by: shortylickens
In reality he should head home. Just because they alwasys tell the truth, doesnt mean they wont rape his punk ass.

:laugh:

 

[amoeba]

never heard the motorcycle variation but the answer is still the same.

"ask either gang what the other gang would say"

 

[YOyoYOhowsDAjello]

Originally posted by: amoeba
never heard the motorcycle variation but the answer is still the same.

"ask either gang what the other gang would say"

:thumbsup:

 

[smc13]

How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

 

[So]

Ask either group to point in all the directions that DISNEYLAND is not in, then your answer is obvious.

 

[joecool]

Originally posted by: smc13
How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

yes, and since the answer is binary (one two possible answers) if you know which answer is incorrect, by inference you also know which answer is correct!

 

[dullard]

Originally posted by: shortylickens
I think the correct answer is ask them both what the other would say to the question of 'Wheres Disneyland?'

That only works if you know one more fact. The gang must know that the other gang always tells the truth or always lies. If the gangs don't know each other, then you are SOL.

 

[shuan24]

Originally posted by: dullard

Originally posted by: shortylickens
I think the correct answer is ask them both what the other would say to the question of 'Wheres Disneyland?'

That only works if you know one more fact. The gang must know that the other gang always tells the truth or always lies. If the gangs don't know each other, then you are SOL.

that is a good point.

 

[Jzero]

Originally posted by: smc13
How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

There is a fork in the road. Presumably you have come from one direction leaving only left and right. Since there are only 2 options, once you've got the wrong answer, you know the correct one.

In fact the complete answer is to ask one gang what the other gang would say if you asked "Which road leads to Disneyland?" and then GO THE OTHER WAY.

That only works if you know one more fact. The gang must know that the other gang always tells the truth or always lies. If the gangs don't know each other, then you are SOL.

The gangs don't really need to know which is which. If I go to Gang A and tell them to ask Gang B which way to go, I will get what I need.

Say the correct answer is "Left."

If Gang A lies, they will ask Gang B and Gang B will say "Left," which is the truth. Gang A will report back to you that Gang B said "Right," because Gang A always lies.

You go left.

If Gang A tells the truth, they will ask Gang B and Gang B will lie and say "Right." Gang A will truthfully respond that Gang B said "Right."

You go left.

 

[amoeba]

Originally posted by: Jzero

Originally posted by: smc13
How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

There is a fork in the road. Presumably you have come from one direction leaving only left and right. Since there are only 2 options, once you've got the wrong answer, you know the correct one.

In fact the complete answer is to ask one gang what the other gang would say if you asked "Which road leads to Disneyland?" and then GO THE OTHER WAY.

That only works if you know one more fact. The gang must know that the other gang always tells the truth or always lies. If the gangs don't know each other, then you are SOL.

The gangs don't really need to know which is which. If I go to Gang A and tell them to ask Gang B which way to go, I will get what I need.

Say the correct answer is "Left."

If Gang A lies, they will ask Gang B and Gang B will say "Left," which is the truth. Gang A will report back to you that Gang B said "Right," because Gang A always lies.

You go left.

If Gang A tells the truth, they will ask Gang B and Gang B will lie and say "Right." Gang A will truthfully respond that Gang B said "Right."

You go left.

you are correct and I did not want to post whole answer in earlier post.

 

[amoeba]

Originally posted by: smc13
How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

you suck at logic.

 

[dullard]

Originally posted by: Jzero
The gangs don't really need to know which is which. If I go to Gang A and tell them to ask Gang B which way to go, I will get what I need.

That is one command, not one question.

I'm being picky yes. But this riddle has been so overdone that nearly everyone knows the answer and we have to go one step beyond to have any intresting thoughts on the subject.

 

[icejunkie]

Originally posted by: shortylickens

In reality he should head home. Just because they alwasys tell the truth, doesnt mean they wont rape his punk ass.

LMAO!!!

 

[Jzero]

Originally posted by: dullard
That is one command, not one question.

I'm being picky yes. But this riddle has been so overdone that nearly everyone knows the answer and we have to go one step beyond to have any intresting thoughts on the subject.

Yeah, you better word the question correctly. If you say "Would you go ask Gang B which road goes to Disneyland?" You're liable to get a "Yes" or a "No."

But whether or not the gangs are aware of their counterparts' truth-telling habits doesn't matter in either case.

But the riddle has been played out since it was depicted in Labyrinth. No question there

 

[smc13]

Originally posted by: joecool

Originally posted by: smc13
How about "Can you tell me which road leads to Disneyland?"

If you have one question to ask why would you ask "Would you tell me what the other gang would say?" If you ask the lying group they will lie to you and if you ask the truth group they will tell you the lie the lying group would have told you. All you will know for sure is that you don't have the correct answer.

yes, and since the answer is binary (one two possible answers) if you know which answer is incorrect, by inference you also know which answer is correct!

But it isn't really binary. They could just as easily lie by saying it is Orlando or point in a direction where there is no road. Why would you expect them to lie in such a way to get you where you are going?

 

[amoeba]

there is a fork in the road, you know one of the paths leads to disneyland.

you ask one gang " which path would the other gang say leads to disneyland?"

and then you take the other path.

if you are afraid of pointing in a direction in which there is no road, you point to a road and ask one gang " would the other gang say this road is the road to disneyland?" if they answer no, take the road you are pointing at. If they say yes, take the other one.

 

[DaveSimmons]

Originally posted by: smc13
But it isn't really binary. They could just as easily lie by saying it is Orlando or point in a direction where there is no road. Why would you expect them to lie in such a way to get you where you are going?

Stated correctly:
One gang ALWAYS lies
One gang ALWAYS tells the truth.
Each gang knows the other gang lies / tells the truth
One of two roads DOES lead to Disneyland

Ask either gang, "Which of the two roads would the OTHER gang SAY leads to Disneyland?"

Write out the two cases on paper, you are always given the wrong road.

 

[91TTZ]

These questions only work on paper. In real life, there would be other variables.

Such as, you ask which road goes to Disneyland:

Gang1: I don't know
Gang2: I don't know either.

The gang that always tells the truth is telling the truth. They don't know. The gang that always lies knows the answer, but they're not going to tell you.

And how many biker gangs go to Disneyland, anyway?

 

[91TTZ]

By the way, these questions are misleading in that they always ask a binary question and that the liars ALWAYS lie. That's sort of against what a liar does. If a liar ALWAYS lied to a binary question, they are in effect always telling the truth, giving the opposite answer very reliably, 100% of the time. A real liar mixes things up so you never know if they're telling the truth or not and you can't get reliable information out of them.

 

[amoeba]

Originally posted by: 91TTZ
By the way, these questions are misleading in that they always ask a binary question and that the liars ALWAYS lie. That's sort of against what a liar does. If a liar ALWAYS lied to a binary question, they are in effect always telling the truth, but with the opposite answer. A real liar mixes things up so you never know if they're telling the truth or not.

er...thanks. these things aren't made to be real world applicable.


this really goes back to the definition of opposites. For example, why is hot the opposite of cold? the 2 are completely the same in every aspect except 1.