Three men go to a hotel to stay over for the night. The clerk tells the men that each room is $30 per night. To save money the three men decide to share one room and each pay $10. Later the clerk relies that the room is really $25 per night and sends the bell boy to return the $5 back to the three men. Not knowing how to split the $5 three ways the bell boy gives each of the men $1 back and keeps the $2 for him self.
Now each man has payed $9 for the room for a total of $27, and the bell boy kept $2 for a grand total of $29. Where is the last $1?