Coasterfrenzy

Click to reveal the correct numbers. First correct was CaptainEd

Unfortunately no. - The numbers on their heads are unique. - Prisoner 3 only knows his number when questioned the 2nd time.

Three prisoners in deathrow are put together. They each get a unique number on their forehead. They are NOT allowed to speak to each other, only to their guard. They only get 2 clues: - The number on their head is always higher than zero - One of the numbers is the total of the other two numbers. If they can guess their numbers, they are free to go. - Person 1 gets asked if he knows his number. He says he doesn't. - Person 2 gets asked the same, but also replies that he doesn't know - Person 3 is being asked but doesn't know either. Since none of them answered wrong. They get another chance. - Person 1 again doesn't know. - Person 2 also doesn't know. - Person 3 however does know the answer this time: It's 148 on his head. This answer is correct and he is allowed to leave. Question: What are the numbers on the heads of person 1 and 2 and how does person 3 know his own number?