Four people are sitting in a row behind one another, all facing forward.
The first man is wearing a green hat,
The second man is wearing a yellow hat.
The third man is wearing a green hat.
The last man is wearing a yellow hat and is blindfolded.
They all know that there are two yellow and two green hats. To win the game, one of them needs to say what colour hat he is wearing. They may not confer or turn around, so they can only see what is in front of them.
After a long pause, one of them shouts out is hat colour. Who was it?
(obvs no guessing involved etc)