|
Is it something along these lines:
If there were four blue hats, then the person with the red hat would be able to leave the room at 12:00.
If there were three blue hats, when no one left the room at 12:00, the two people wearing red hats could leave at 13:00 (because the other person wearing a red hat would have figured out he wasn't in blue when I didn't leave an hour earlier).
If there were only two blue hats, then the three people wearing red hats could leave at 14:00.
If there was only one blue hat (mine), then everyone else could leave the room at 15:00.
So everyone knows s/he's wearing a red hat and they all leave at 16:00.
|