Little Johnny - An Orgy!!

One day in class, the math teacher Mrs. Brown noticed that Little Johnny was not paying attention to what she was saying. So she called Little Johnny to recite in class.

"Little Johnny, answer this math question," she said. "If you have 500 dollars and you gave 100 dollars to Susie and gave 100 dollars to Jeannie and gave 100 dollars to Mary Ann, what do you have ?" 

"An orgy," answered Little Johnny.