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sarveshgupta
sarveshgupta • Jun 4, 2009

Solve this one

There were three guys namely Chester , Mike n Rob they all are
considered as the the most logical persons . To decide among themselves
that who is the most logical person they went to a master called Rick
Rubin .
So what Rick did is that he marked their foreheads with a colored
dot , the dot marked is either of red or black in color . Nor Chester
nor Mike and neither Rob knows that what color dot they are having on
their own forehead but each one of them knows the color of the dot of
other 2 persons forehead .

Then Rick asked them to raise their hands if they see at least one red
dot on other two persons forehead , all three of them raised their
hands .

Then rick asked them to tell the color of the dot they are having on
their forehead. The one who answer the correct color and explain the
correct logic for their answer is the most logical guy. But their was a
silence for a little time no one of them is not able to answer the
color they are having on their forehead then after a while Chester
answers the correct color that he is having on his forehead .
So can you explain what color is Chester having on his forehead and explain the correct logic for it.
shalini_goel14
shalini_goel14 • Jun 4, 2009
Chester was having black colour dot on his head.

Reason: Two dots are marked in Red by Rick so as to make conditon "Everyone can see atleast 1 red colour dot in front of them" true so Mike and Rob each one marked with read colour dot and when Chester see both the red colour dots are in front of him , so black colour dot is on his head itself.

Am I right? 😔
sheeko
sheeko • Jun 4, 2009
chester have a red dot

the others : one have a red dot and the other one have a black dot

because who have a red dot raise his hand while the other one have a black dot

wish i'm right 😉
sheeko
sheeko • Jun 4, 2009
if i was right this competition isn't fair as the guy with the black dot will never be able to know his color
Is the question proper?

Am not getting the trick for silence initially before answering?
sarveshgupta
sarveshgupta • Jun 5, 2009
@shalini: i said all three raised their hands.. so all of them are seeing a red dot atleast..you said since mike and rob see a red dot each chester will have a black dot..but how can he be sure that he doesnot have a red dot too...So you are wrong

@sheeko: your answer is correct but your logical reason is wrong
sarveshgupta
sarveshgupta • Jun 5, 2009
anyways buddies...enough of your guessing games!!!most of ur logics dont make sense...here is the final answer!!!!

Chester answered he was having red dot .....

now lets see how it comes.....
as all three saw at least 1 red dot,its clear that there were two red dots,one black or all 3 red dots....

now suppose chester was red & out of other two,one was black & other was red ,then chester should be able to tell his color 'immediately' bt so should be the other person having other red dot....

next case...chester black...both other red..in that case..both others can tell their colors immediately,bt chester can never be sure whether he is black or red!!!

so the only case remains all 3 are red!!!

now why only chester answers after pondering 4 sumtym bcoz he is the most logical person!!!(@EnglishScared:this is the answer to the problem you were facing..may sound wierd..But it is the logic)
shalini_goel14
shalini_goel14 • Jun 5, 2009
sarveshgupta
@shalini: i said all three raised their hands.. so all of them are seeing a red dot atleast..you said since mike and rob see a red dot each chester will have a black dot..but how can he be sure that he doesnot have a red dot too...So you are wrong
Man, you said they raised their hands when they can see "atleast" one red dot . That means even if one looks one red and other black or as both red, then also they could raise their hands. This was the case I took.

Anyways thanks for the answer sharing.
sarveshgupta
sarveshgupta • Jun 6, 2009
@shalini: But i gave you the reason for why it cant be two red and one black

please read the answer again..
Dude i have a question here .

The person who is having black dot can see both the red dots Ok?

So he can directly answer that he is having black as atlest one is said and total 2 reds are said.
He can see both ?

Please explain i didnt get 😔

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