A guy just got out of prison after being busted for making fake money. His partner wasn't too bright, yet somehow managed to stay out.
So he decided to get back in business. He got with his partner again and they set up the printing presses. They were all set to make 20's. So the guy goes out to get some lunch.
When he comes back his partner had printed up all the money and used up all the ink and paper. He took a look at the money. They were all 18$ bills.
The man said, "Darnit, how could you be so stupid? Ok, I have an idea. We'll take it to some dumb convienence store clerk in Arkansas and trade it out for real money."
They travel all the way to arkansas and find a convenience store. The Man walks in and asks if he could get some change for his money. He hands over a few of the 18 dollar bills.
The clerk then asks, "Do you want this in 3 6's, or 2 9's?