Joke: Answer Question

The professor and the farmer were sitting opposite each other on the train, bored.

The professor said, "I have a problem, if you don't know, give me 5 yuan."

If you come up with a problem and I don't know, how about giving you $500?

The farmer agrees.

The professor asked: How far is the moon from the earth?

The farmer handed the professor $5 without a word.

The farmer asked: Three legs up the hill, four legs down the hill, what animal is it?

The professor thought hard and had no solution, but gave the farmer 500 yuan.

The farmer took the money and got ready for bed.

The professor asked: What animal is it that has three legs up the hill and four legs down the hill?

Without a word, the farmer handed the professor five yuan and went to sleep.