Three Towns Forum

Members' Lounge => Games, Jokes & Quizzes => Topic started by: Ian on December 21, 2012, 09:05:08 pm

Title: Christmas brain teasers...
Post by: Ian on December 21, 2012, 09:05:08 pm
To help unfuddle the brain from all the mince pies and sherry...

"Three gods A, B, and C are called, in some order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a completely random matter. Your task is to determine the identities of A, B, and C by asking three yes-no questions; each question must be put to exactly one god. The gods understand English, but will answer all questions in their own language in which the words for 'yes' and 'no' are 'da' and 'ja', in some order. You do not know which word means which."
Title: Re: Christmas brain teasers...
Post by: Ian on December 21, 2012, 09:14:26 pm
A few hints...

    1. It could be that some god gets asked more than one question (and hence that some god is not asked any question at all).

    2. What the second question is, and to which god it is put, may depend on the answer to the first question. (And of course similarly for the third question.)

    3. Whether Random speaks truly or not should be thought of as depending on the flip of a coin hidden in his brain: if the coin comes down heads, he speaks truly; if tails, falsely.

    4. Random will answer ‘da’ or ‘ja’ when asked any yes-no question.
Title: Re: Christmas brain teasers...
Post by: Yorkie on December 21, 2012, 09:57:00 pm
Boolo to you Ian!  C29 Logic x 3
Title: Re: Christmas brain teasers...
Post by: Merddin Emrys on December 21, 2012, 11:03:37 pm
Well I googled the question and found lots of answers, yet still I have no idea about it! No wonder I'm unconvinced about the Lunar landing story! Has the world ended yet?  :laugh:
Title: Re: Christmas brain teasers...
Post by: Fester on December 22, 2012, 01:07:27 am
Ian!! Why must you hurt my feeble brain in this way?

After questing the existence of God, I started to question my own existence.
Then I began to question existence itself.
Finally, I questioned the existence of Yorkie, Google and Merddin Emrys..... then went to bed, demoralised.
Title: Re: Christmas brain teasers...
Post by: Ian on December 22, 2012, 08:20:08 am
Quote
Well I googled the question and found lots of answers, yet still I have no idea about it! No wonder I'm unconvinced about the Lunar landing story!

 _))* _))* _))*

The answers - such as they are - run to some five pages in length, so I'll only reprint them if enough folk truly want to know.
Title: Re: Christmas brain teasers...
Post by: Yorkie on December 22, 2012, 11:27:06 am
As I said Boolos, Logic, logic, logic.  Chapter 29. or try

http://www.hcs.harvard.edu/hrp/issues/1996/Boolos.pdf (http://www.hcs.harvard.edu/hrp/issues/1996/Boolos.pdf)

 D)
Title: Re: Christmas brain teasers...
Post by: Yorkie on December 28, 2013, 05:45:17 pm
.
Title: Re: Christmas brain teasers...
Post by: Merddin Emrys on December 28, 2013, 05:52:26 pm
 _))* and yes we did!  ;D
Title: Re: Christmas brain teasers...
Post by: Nemesis on December 29, 2013, 08:30:23 am
I have always liked and done crosswords, but anything logic has my brain aching.--- It aches! ???