This is not my own joke; I got it from a fellow colleague.
There was once an arrogant American who was seated next to an Indian man in an airplane. They were flying to Los Angeles from New Delhi, so the flight was going to be quite lengthy. Therefore, the American decided he would try to get to know his fellow seating partner with a small game.
The American started, "Excuse me, good sir. Would you be up for a small betting game?"
The Indian looked up from his magazine and studied the American's jubilant face. He answered, "Sure. What do you propose?"
"Let's have a battle of wits. We will each ask the other a question, like a riddle of sorts. If you cannot answer the riddle, you must pay up five dollars. But, if you can and get it right, the riddler must pay up instead."
"Only five dollars?" The Indian seemed unconvinced that the game was worth his time.
Not wanting to lose his audience, and perhaps too confident in his intelligence, the American responded, "Wait, how about this. Instead of five dollars, we'll make it fifty." The Indian shook his head and picked up reading from where he stopped earlier. "Alright, alright. I'll pay you five hundred dollars, but you only need to pay fifty. C'mon, this is completely in your favor."
The Indian looked up from his magazine once again and cocked his head. An arrogant American indeed. "Very well. You have yourself a bet."
The American glowed with glee. "Excellent! You ask first."
The Indian thought for a moment before giving his riddle, "What starts up a mountain with four legs, reaches the summit with three, then climbs down with two?"
What kind of question was that? Let's see… four legs… well, that could be someone climbing with hands and feet, then when they climb back down… no. They would still need all four limbs. What about the three legs? What on earth has three legs…
At last, after several minutes of silence and sweat, knowing what was on the line, the American conceded. "I can't answer. You win." He regretfully handed the Indian a five hundred dollar check. "What was it?"
The Indian gave the American fifty dollars back.