Instead of two red and two blue hats there are 3 hats of one colour and only 1 hat of another, and the 3 prisoners can see each other i.e. C calls out that he is wearing a black hat. “An executioner lines up 100 prisoners single file and puts a red or a blue hat on each prisoner’s head. If the two front hats were black, the third wise man would have called out the colour of his hat as white immediately. Now Dave placed a hat on the head of each of his three friends, putting aside the remaining two hats. This is because D can't answer, and neither can A or B. Abe said he couldn’t tell. B can't see anyone and also can't determine his own hat … Each hat can be red or blue at random. The prisoners can see the hats of the people lined up in from of them, but they cannot look at the hats behind them, or at their own. After a while, C comes to the realization that he must answer. There are 5 hats. There were 4 people sitting in a row, trying to win $50 from a riddle. Prisoners in a line wear red or blue hats; each must identify his color to live. D can see C and B, but can't determine his own hat color. The third from the front was wearing a red hat. Starting at the back of the line, the executioner asks the last prisoner to state the colour of his hat. What strategy maximizes the number of survivors? Three hats are placed on the heads of three men standing in a line. Each man is asked if he knows which color hat he … If you see both a red and a blue hat, then “pass” If you see two red hats, then guess “blue” If you see two blue hats, then guess “red” This strategy wins in all six cases with at least one hat of each color. Three of the hats were blue and two were red. A very nice riddle. A sees B & C, B sees A & C and C sees A & B. The one in front was wearing a red hat. Puzzle : Prisoners and Four - hats. It only loses in the two cases of all-red or all-blue, in … If there are infinitely many.red hats, everyone will guess red, and the players with red hats will be correct; if 20 THE MATHEMATICAL INTELLIGENCER 9 2008 Springer Science+Business Media, Inc 100 prisoners are lined up by an executioner, who places a red or blue hat upon each of their heads. In this riddle, we are assuming that everyone is equally smart. The last was wearing a blue hat and is blind-folded. The second from the front was wearing a blue hat. Then he asked Abe what color his hat was. Nobody knows the color their hat will be before the game starts. They say out loud that they cannot determine what color hat they have one. Share. So 3 people are sat down at a table, numbered 1, 2, and 3. In addition, the men all know that the hats came from a bag with 3 red hats and 2 blue hats. Seems important to state any assumptions that may be missed in the problem as well. Everyone closes their eyes, and Person #1 opens their eyes and looks at the two other people wearing hats. Cite. If the first hat were black, and the third man did not call out any colour, the second wise man could deduce that his hat was white. Then he asked Abe what color his hat was. Each person will be able to see the hat of everyone in front of them, but won't be able to see the hats of anyone behind them. Each person then receives a hat on their head. Now the same puzzle with different condition. red if he sees infinitely many red hats, and guess blue oth- erwise. 3 red hats, and 2 blue hats. Each man can only see the men and hats in front of him. Everyone can hear everyone else. There is a similar puzzle here with a pretty well explained solution as well: Prisoner Hat Riddle. Dave had 5 hats which he showed to his three friends. Why is he 100% certain of the color of his hat? Three of the hats were blue and two were red. 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