Puzzle of the week - 20th Nov to 26th nov 2006

Hi all,

Happened to see this puzzle... liked it... hope u try it

4 men in hats





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Shown above are 4 men buried up to their necks in the ground. They cannot move so can only look forward. Between A and B is a brick wall which cannot be seen through. They all know that between them they are wearing 4 hats, 2 x black and 2 x white, but they do not know what colour they are wearing. In order to avoid being shot one of them must call out to the executioner the colour of their hat. If they get it wrong, everyone will be shot. They are not allowed to talk to each other and have 10 minutes to fathom it out.
After 1 minute, one of them calls out.
Question: Which one of them calls out?
Question: Why is he 100% certain of the colour of his hat?
This is not a trick question. There are no outside influences nor other ways of communicating. They cannot move and are buried in a straight line. So A & B can only see their respective sides of the wall, C can see B, and D can see B & C .

If some of u know the answer..coz u have seen it before... try to hold back posting the answer.... so that others enjoy solving it....

priyum

 

Are u ready for the answer

Hi friends,

40 views and no replies. I assume that most of u know the answer and were holding back for a while (probably I should not have inserted that clause ) ...

I would like if someone posts the answer. (atleast theriyalaina theriyalainu sollungo pa ...)

Priyum

 

Hi Sunkan,

Could u explain, why u feel its D.

Priyum

 

Hi Sunkan,

D is wrong. He knows the color of the Hats of B and C. But how will he know the color of his hat?

priyum

 

out with the answer

Hi Sunkan,

i am posting the answer ( but what baffles me from ur post is if D can look up and see his hat's color, why can't the others do that ? (and then where is the puzzle?) Now u puzzle me , or where u just teasing ?)

Waise, to be truthful, I too could not fathom the answer to this puzzle... but i found it interesting.

Answer<SCRIPT type=text/javascript>showSHToggle("show","hide",1)</SCRIPT>

C calls out that he is wearing a black hat. Why is he 100% certain of the colour of his hat ?
After a while, C comes to the realization that he must answer.
This is because D can't answer, and neither can A or B.
D can see C and B, but can't determine his own hat colour. B can't see anyone and also can't determine his own hat colour. A is in the same situation as B, where he can't see anyone and can't determine his own hat colour.
Since A, B, and D are silent, that leaves C. C knows he is wearing a black hat because if D saw that both B and C were wearing white hats, then he would have answered. But since D is silent, C knows that he must be wearing a black hat as he can see that B is wearing a white hat.