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## Question

There are three people A,B and C from one amazing island. One of them always speaks the truth, one of them always lie and one lies one day but speaks truth the other day. There is one more problem, they can't speak english (but they can understand) and so far we have known that "Da" and "Ja" in their language means YES and NO in some order.

By asking them only three questions how can you determine their identity?

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There are three people A,B and C from one amazing island. One of them always speaks the truth, one of them always lie and one lies one day but speaks truth the other day. There is one more problem, they can't speak english (but they can understand) and so far we have known that "Da" and "Ja" in their language means YES and NO in some order.

By asking them only three questions how can you determine their identity?

If you ask all three the same question does that count as one question or three?

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[1] Ask A: is B more truthful than C? [Honestant is most, and Swindlecant is least, truthful]

[2] Ask B: Is A more truthful than C?

Four cases:

Yes-Yes -> C is not the Randomcant. Could be any of ABC, BAC, CAB, CBA.

Can't resolve this with a single question.[-*-]

Yes- No -> B is the RC.

[3] Ask C: Would A say you tell the truth? Yes -> ABC; No -> CBA.

No - Yes -> A is the RC.

[3] Ask B: Would C say you tell the truth? Yes -> CAB; No -> BAC

No - No -> C is the RC.

[3] Ask A: Would B say you tell the truth? Yes -> BCA; No -> ACB

Where the order in each case is Honestant / Randomcant / Swindlecant.

[-*-] Back to the drawing board.

Edit: This spoiler assumes Da means Yes.

Re-reading OP, I can't assume that.

Now I'm wondering whether we can ask each of them 3 questions.

But that would be too easy.

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Clarifications for the question.

1.You are strictly allowed to ask only 3 questions.

(no matter, you ask all 3 to same person or one to each OR Ask same question to 3 different person

i.e. Each Yes/No reply counts as one question)

Hint: You must ask Yes/No question since you can understand reply only in Yes/No format.

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Does "Da" mean Yes and "Ja" mean No? Or does "Da" mean No and "Ja" mean Yes? Or is it unknown which of those two cases it is?

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Does "Da" mean Yes and "Ja" mean No? Or does "Da" mean No and "Ja" mean Yes? Or is it unknown which of those two cases it is?

I think the OP implies we don't know. "in some order"

This is either a difficult or an impossible riddle.

[1] Ask questions on successive days and note if an answer changes.

[2] Those probably have to be the first two questions.

What's learned [which one means "yes"] can then be used to decide what to ask for Question #3.

Edited to put my speculation into a spoiler.

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A colleague has put me onto an approach that makes it not necessary to know whether Da means Yes or No.

This isn't my result, but I'm posting it for others to use. Group effort and all ...

A [Da/Ja] response to Y is logically equivalent to a [Yes/No] response to X!

[1] regardless of the Yes/No meaning of Da

[2] regardless of whether the responder is lying [sC or RC on a bad day] or telling the truth [HS or RC on good day]

The problem is now simplified.

We [just] need 3 Yes/No questions which if answered correctly will tell us who is who.

Check it out:

| X would be Yes | Da=Yes | is truthful | question Y |
+----------------+--------+-------------+------------+
| T | T | T -> Da |
| T | T | F -> Da |
| T | F | T -> Da |
| T | F | F -> Da |
+----------------+--------+-------------+------------+
| F | T | T -> Ja |
| F | T | F -> Ja |
| F | F | T -> Ja |
| F | F | F -> Ja |
+----------------+--------+-------------+------------+
`+----------------+--------+-------------+------------+`

Which means post #3 is now back to being a near-miss.

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Here is a clarification and a hint.

We don't know whether "Da" or "ja" means YES and oviously whether "Da" means NO or "ja" means NO

Hint:

You can ask questions containing the words "Da" or "Ja"

for eg. "Do you say "da" if i ask you does sun rise in the east"

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Thanks wise_rajendra, this was a great puzzle. [i'm curious whether you read post #7]

Here's one for you.

If I ask you 'is B a RC?' would you say 'Da'?

If A answers 'Da' C is not a RC. Call C NRC1 [not RC 1] and call B 'Beta'.

If A answers 'Ja' call B NRC1 and call C 'Beta'.

If I ask you 'is A a RC?' would you say 'Da'?

If he answers 'Da' then 'Beta' is NRC2.

If he answers 'Ja' then A is NRC2 and 'Beta' is RC.

If I ask you 'is NRC2 a HS?' would you say 'Da'?

If he answers 'Da', NRC2 is HS and NRC1 is SC.

If he answers 'Ja', NRC2 is SC and NRC1 is HS.

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