Math!!! It Isn't So Straightforward

Math seems pretty straightforward. And it's either simple calculations or complex ones. But there is always a solution...Or is there!!!

Let's try this. (figures are just examples and are not reflective of any rates. *grin*)

3 guys who were traveling stopped at a motel for the night. They got a not-so-expensive room for themselves, which cost them $30. So each guy had to shell out $10. This seemed to be a good deal for a stay there.

Just before checking out in the morning, room service came by and told them that the manager had given them a $5 discount. He returned the same to them. The 3 guys each took $1 back and tipped the room service guy with the remaining $2. And off they went headed back home.

Now let's go back and calculate the equation!!!
Each guy 1st spent $10, but took back $1 later. So in the end each spent $9. So 3x9=27. And the room service guy was tipped $2. So 27+2=29.
Hmmmm!!! $29 has been accounted for. So where is that remaining 1 dollar???

Math!!! Simple, but sometimes, complicated, or shall we say, Mind Boggling!!!