Jane Street–styleInternInternshipQuestion #591
There are one hundred doors, each with one dollar behind it. You roll a one-hundred-sided die one hundred times. After rolling, you may take the dollar behind the door corresponding to any number that was rolled. What is the expected amount of money you can obtain? Explain why.
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More Jane Street–Style Intern Questions
Design a real-time system to process millions of trades per second. How would you ensure low latency, fault tolerance, and exactly-once processing?If I roll two dice, what is the expected value of the product of the two faces?Suppose we play a game with a die where we roll and sum our rolls. We can stop at any time, and the sum is our score. However, if our sum is ever a multiple of 10, our score becomes zero and our game is over. What strategy will yield the greatest expected score? What about if the target multiple is a value other than 10?Implement the game Tetris in 30 minutes.What is the optimal strategy for winning in rock-paper-scissors if your opponent can only choose between rock and paper?
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