An arrogant professor boards a plane and gets a seat beside an old man.
Mid-flight, the professor decides to play a game with the old man and prove he’s intellectually superior, so he turns to him and says:

“Hey, do you want to play a little game with me?”
The old man looks at him and says: “Depends. What type of game?”
The professor goes on to explain the game:

“Taking turns, we’ll ask each other one question at a time. If the other knows the answer, the asker gives him one dollar, and if he doesn’t, he gives one dollar to the asker. Want to play?”
The professor grins, knowing his general knowledge is vastly superior.

To his dismay, the old man refuses! Determined to make him agree, the professor raises the stakes for him.
“If I lose, I ‘ll give you two dollars instead of one!”
“No.”
“Five dollars!”
“No.”
“Ten dollars!”
“I told you, no.”

Desperate, the professor makes one final offer: “If I lose, I’ll give you a hundred dollars, and if you lose you’ll only give me one!”
The professor pleads. The old man ponders this, and then sighs. “Only if I get to start”, and the professor immediately agrees.

“Ask away”, the professor says, confident he’ll never lose.
The old man asks: “What has five heads, forty feet, and lives inside of a bucket?”
The professor turns the riddle over in his head, trying to find anything that fits the description.
After an hour of intense concentration, the professor gives up. G rumbling, he pulls out his wallet and gives the old man $100.

He wastes no time and asks him: “So what has five heads, forty feet, and lives inside of a bucket?”
The old man smiles, shrugs and says:
“I’ve got no idea. Here’s your dollar.”