Question

In the county jail, 4 prisoners A, B, C, D are selected and D is blind. The sheriff Anne Oakley puts blindfolds on A, B, and C since D is already blind. Next she selects four hats from seven hats hanging on the hat rack, three of them are red and the other four are white. She places four hats on the prisoner’s heads and hides the remaining three hats. Then she takes the blindfolds off A, B, and C and tells what she has done, including the fact that there were three red hats and four white hats to choose from. Sheriff Oakley then says, “If you can tell me the color of the hat you are wearing, without looking at your own hat, you can go free.” The following things happen: 1. A says that he can’t tell the color of his hat. So the sheriff has him returned to his cell. 2. Then B says that he can’t tell the color of his hat. So he is also returned to his cell. 3. Then C says that he can’t tell the color of his hat. So he is returned to his cell. 4. Then D, the blind prisoner, says that he knows of the color of his hat. He tells the sheriff, and she sets him free. What color was D’ hat, how did D do his reasoning?

Answer 1