I've got one. Three guys go to a hotel and want to rent a room. They are charged $30 for the room, so they split it, $10 each. When they get in their room the hotel manager realizes he forgot to give them the special weekday rate of $25, so he gives the bell hop $5 and tells him to take it to the three guys. The bell hop, knowing that three guys cant split $5 evenly, pockets $2 himself, and gives $3 to the guys. So each guy has paid $9 for his share of the room, and the bell hop has $2.
9 X 3 = 27
27+2=29.
What happened to the other dollar?