There are 'N' people in a room, each wears a birthday hat of a specific colour. They can see other people's hats but not their own. 4. Solve the puzzle: One of them shouted "If you can see at least 6 yellow hats and at least 6 white hats, raise your glass" Exactly 12 people raised their glass what is the possible value of 'N' that fits the case?​