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# The liar, the truth teller....and the random answerer

Best Answer Writersblock , 30 July 2007 - 01:31 AM

Martini,

Spoiler for ...
Go to the full post

94 replies to this topic

### #21 staggy

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Posted 31 March 2008 - 10:46 AM

Lets say there are three people A, B and C.

Q1: Ask B: If i ask A if he is a toggler (S) will he say yes?
Three possibilities: (i) No answer (ii) No (iii) Yes.

You get no answer for the following combinations: A is S, B is L; A is S, B is T.
As you see is the above combinations A is always S.

Q2: AskB: Is A a toggler?
Two possibilities: Yes or No
Since we already know A is S, if the answer is Yes then B is T and C is L. END
If the answer is No then B is L, C is T and A is S. END

For this option we find out who is who with only two questions. Lets see the other options to the first question:

(ii) No
You get No for the following combinations: A is T, B is S (1); A is L, B is S (0) /* S (1) and S (0) implies that the toggler told the truth or a lie respectively for the first question.

Q2: Ask A: Is B a toggler?
Two possibilities: Yes or No. If yes, A is T, B is S, C is L. END
If No, A is L, B is S, C is T. END

We also find out who is who in this case in two questions. The last option of the first question will need three questions shown below.

(iii) Yes
We get yes for the following combinations: A is T, B is S (0); A is L, B is S (1); A is T, B is L; A is L, B is T.
Q2: Ask B: Is A a liar?
Two possibilities: (a)Yes or (b)No
(a)Yes
the combination are: A is T, B is L; A is L, B is T.
Q3: Ask B: If I ask A if u r a liar would he say yes?
Yes: A is L, B is T and C is S. END
No: A is T, B is L, C is S. END

(b) NO
Combinations are: A is T, B is S; A is L, B is S.
Q3: Ask A: is B a toggler?
Yes: A is T, B is S, C is L. END
No: A is L, B is S, C is T. END
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### #22 Multee-Pass

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Posted 08 April 2008 - 11:12 PM

NICE

Edited by Multee-Pass, 08 April 2008 - 11:14 PM.

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### #23 Corpuscallosum

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Posted 30 April 2008 - 10:56 PM

Ask one man if he is a man. If he says yes, he is either the random or the truthteller. If he says no, he is the liar.

Ask a second man if he is a man. If he says yes, he is either the random or the truthteller. If he says no, he is the liar.

If one of the first two answers you get is no, then that man is the liar, and ask him which of the other two men is the truthteller. Whichever man he chooses is the random, and the last man is the truth teller.

If the first two answers you get are Yes, then ask the third man, who must be the liar, which if the first two men is the truthteller. Whichever man he chooses is the random, and the last man is the truth teller.
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### #24 Scraff

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Posted 30 April 2008 - 11:57 PM

If one of the first two answers you get is no, then that man is the liar.

Not necessarily. He may be the random answerer.
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### #25 kcb

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Posted 05 May 2008 - 04:44 PM

This is how I worked it out.

People:
A B C

To person B: Are you a liar?

Go to person C and ask "Is person B the random answerer"
C = Truth Teller
C = Liar

B = Random Answerer or Truth Teller
Go to person C and ask "Are you a liar?"
B= Truth Teller
A = Liar

A = Liar
Ask person C "Are you the truth teller?"
B = Truth Teller
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### #26 scuttill

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Posted 05 May 2008 - 04:57 PM

All I have to say is that if I am ever stranded on an island with but only one way to sure escape, caught behind two locked doors with one leading to certain death, being boiled alive in lava with one shot to ask a question to get me out, ... I want Writersbloc in my party ... Well done, indeed, as I was about to give up and decided to scan for other responses.
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### #27 Gaunt

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Posted 06 May 2008 - 11:23 PM

Spoiler for My Solution

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### #28 Asdfgh Zxcvbn

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Posted 07 May 2008 - 01:52 AM

Hello Ppl. Whats up. I hope im not copying anyone with this answer, and if i am im terribly sorry. Now here's my answer

Spoiler for truth,lies,random

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### #29 Asdfgh Zxcvbn

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Posted 07 May 2008 - 02:02 AM

Sorry if i didnt mention this, because i know people will try to say "what if you are in a room and there is no way to tell where the sun is right now"

Well, the question i gave was an example of a good question.

A type of question you need to ask is something you know the answer to, and so do the 3 ppl (T,L,B)

you could ask the colour of something or ask where you 4 ppl are in the world

as long as it is something that all 4 of u ppl know the answer to
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### #30 Martini

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Posted 07 May 2008 - 02:20 AM

Spoiler for My Solution

There are actually two men who can't answer, not one, so the solution the way you proposed it won't work. Also, it assumes that not answering is permissable, so the random answerer can also choose not to.

Hello Ppl. Whats up. I hope im not copying anyone with this answer, and if i am im terribly sorry. Now here's my answer

Spoiler for truth,lies,random

"if B says yes, then you ask the L (the only one that lied) who the T is"

What if two of them lied?
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