You do the Math!

Where the Buck Stops
Three guys in a hotel call room service and order two large pizzas.
The delivery boy brings them up, with a bill for exactly $30. Each guy gives the boy a $10 note and he leaves. That's fact!
When the boy hands the $30 to the cashier, he is told a mistake was made. The charge was only $25, not $30. The cashier gives the boy five $1 coins and tells him to take it back to the three guys who ordered the pizzas. That's fact!
On the way back to their room, the delivery boy has a thought. These guys did not give him a tip. He figures that since there is no way to split $5 evenly into three, that he will keep $2 for himself and give back $3. OK! So far so good....
The boy knocks on the door and one fellow answers. He explains about the mix-up, and hands the guy $3, and then departs with the $2 tip in his pocket. Now the fun begins!

Remember, $30 - $25 = $5, right? $5 - $3 = $2, right? So whats the problem? All is well, right?

Not quite. Answer this: Each of the three guys originally gave $10 each. They each got back $1 in change. That means they paint $9.00 each, which times three is $27.
The delivery boy kept $2 for a tip. $27 + $2 = $29. Where the heck is the other dollar!?

'Till next time...