Question of The Day

Three wise men are told to stand in a straight line, one in front
of the other. A hat is put on each of their heads. They are told
that each of these hats was selected from a group of five hats:
two black hats and three white hats. The first man, standing at
the front of the line, can’t see either of the men behind him or
their hats. The second man, in the middle, can see only the first
man and his hat. The last man, at the rear, can see both other
men and their hats.
None of the men can see the hat on his own head. They are
asked to deduce its color. Some time goes by as the wise men
ponder the puzzle in silence. Finally the first one, at the front of
the line, said " I Know".
How did he know the colour of his hat and what colour is it?

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