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?

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