All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Logic > Liars and Knights
Only One Question (Posted on 2005-02-16) Difficulty: 3 of 5
The following two facts are known about Adam, Bert, and Carl:

1) Of Adam, Bert, and Carl, there is one knight, one knave, and one liar.
2) Adam said once, "Bert said that Carl isn't a knight."

Can you ask one yes/no question to one person and figure out who is who? If not, how many questions must you ask?

See The Solution Submitted by Dustin    
Rating: 4.0000 (8 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
(-) * (+) = - | Comment 16 of 23 |

could anyone define (KNAVE)!!

i don't know exactly what does it mean

is he the person who sometimes lies and somtimes tells the truth? that' it?

 

another thing, I use math for this problem and it's useful so far, I mean when you put the Lie as (-) and the truth (+)

and as (-) * (+) =( -) & (+) * (-) =( - )

also (-) * (-) = + & (+) * (+) = +

Adam said once, "Bert said that Carl isn't a knight." 
 the possibility of its truth( I mean the statment not a lie)  is ONE

that's true only if Adam is a KNIGHT and Bert is a KNAVE who chose the truth this time, or  Adam is the knave , Bert is the knight, and Carl is the LIAR,in this situation we just ask Carl about Adam and take the opposite of his answer

-------------------------

If the statment is wrong (lie)  as :

Adam(-) *   Bert (+) = -

Adam (+) *  Bert(-)= -

that means the answer is a lie

and Carl is really a KNIGHT,

we just go and ask him about Adam, and we take his answer

I'm working this way,

and I'll try to find the best key

 

good luck

Edited on February 27, 2005, 8:54 am
  Posted by turki on 2005-02-26 18:49:05

Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (8)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information