Devil
A mathematician, a philosopher, and a blonde all go to Hell and receive a challenge from the Devil -- if they can stump him, they're free to go to heaven instead. The philosopher goes first and asks the Devil a very hard philosophy question -- to which the Devil snaps his fingers, gets a book, and gives the answer. The mathematician tries as well -- but the Devil instantly gets the answer. When it comes to the blonde, she pulls up a chair and drills three holes in it. She then sits down in the chair and farts.
"Now," she says, "which hole did the fart come out of?"
"That's easy," says the Devil. "All of them."
"No, stupid! It came out of my butthole!"