Three guys split the cost of $30. They each kick in $10. The manager tells the clerk the room is only $25. He hands five $1 bills to the clerk and tells him to refund the money. The bell hop says to himself, "No way can three guys split $5, I'm going to help out." He stuffs $2 in his pocket, knocks on the door, gives each guy back a buck. So now each guy has paid $9. $9 times 3 is $27 plus $2 the bell hop stole--only $29! Where is the other buck?