Solution to: 3 Heads & 5 Hats
The answer: man A is wearing a white hat.
From the fact that neither B nor C gives an answer, we conclude that both these men have insufficient information to determine the color of their hats. Let us start with man C. He must be seeing at least one white hat on the heads of A and B (if he would see two black hats, he would know that he is wearing a white hat). Man B therefore knows that he and/or A is wearing a white hat. Since he cannot give an answer, he must be seeing a white hat on A's head (if B would see A wearing a black hat, he would know that he himself wears a white one). From the fact that neither C nor B can give an answer to the jailer's question, A finally concludes that he is wearing a white hat!