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#1 bonanova

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Posted 16 February 2008 - 02:56 AM

In the land of Knights, Knaves and Liars [KKL]
Knights always tell the truth,
Knaves alternate telling the truth and lying: e.g. T F T F or F T F T and
Liars, of course, always lie.

Al and Bob are Knaves. They make the following statements.
You don't know who made which statement, but you know the time sequence is correct.

Edit: Al and Bob each made four statements.

1. Chuck is a liar.
2. Dave is a Knave.
3. Elliot is a Knight.
4. Chuck and Dave are the same type.
5. Dave and Elliot are of different types.
6. Chuck is a Knight.
7. Elliot is a Knave.
8. Dave is a liar.

Identify Chuck, Dave and Elliot as a Knight, Knave or Liar. They might all be of different types, but they needn't be.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#2 PolishNorbi

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Posted 16 February 2008 - 03:32 AM

Spoiler for Spoiler?

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#3 sk8rkat

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Posted 16 February 2008 - 03:35 AM

i think that
Chuck is a knight
Dave is a knave
Elliot is a liar
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#4 bonanova

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Posted 16 February 2008 - 03:57 AM

i think that
Chuck is a knight
Dave is a knave
Elliot is a liar

That would make statements 1,2,3,6,7,8 = F T F T F F so that statements 4,5 would be T T.
Thus C=D^=E.
Chuck and Dave would be the same.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#5 Aatif

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Posted 18 February 2008 - 06:22 AM

One possible solution is:
Chuck = Knave; Dave = Knave; Elliot = Knave

Spoiler for All about the Knights & Liars

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#6 Aatif

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Posted 18 February 2008 - 06:31 AM

One possible solution is:
Chuck = Knave; Dave = Knave; Elliot = Knave

Spoiler for All about the Knights & Liars


I rechecked my logic and it seems there are multiple solutions possible.
Another one can be:
Chuck is Knight; Elliot is Knight and Dave is Liar

Spoiler for Multiple sols

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#7 bonanova

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Posted 18 February 2008 - 06:37 AM

One possible solution is:
Chuck = Knave; Dave = Knave; Elliot = Knave

I rechecked my logic and it seems there are multiple solutions possible.
Another one can be:
Chuck is Knight; Elliot is Knight and Dave is Liar

There are 8 statements to work with.
Did you use all of them?
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#8 Aatif

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Posted 18 February 2008 - 06:38 AM

There are 8 statements to work with.
Did you use all of them?

After All that hard work .. I get this .. URGHHHH!
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#9 Aatif

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Posted 18 February 2008 - 06:47 AM

After All that hard work .. I get this .. URGHHHH!


Ok.. Now I include statement number 5, which I blissfully ignored in my 2 earlier posts :blush:

Solution 1:
Chuck = Dave = Elliot = Knave
Spoiler for Not much change


Solution 2:
Chuck is Knight; Elliot is Knight and Dave is Liar
Spoiler for Not much change

Edited by Aatif, 18 February 2008 - 06:47 AM.

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#10 bonanova

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Posted 18 February 2008 - 09:13 AM

The solution is not ambiguous if I include the information that Al and Bob each made four statements.

My bad ... :blush:
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell




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