Jane Street–styleInternInternQuestion #529
1) What is 12% of 47? 2) If I pick 2 cards from a shuffled deck (with no jokers), what is the probability that both are queens? 3) i) If I toss 4 fair coins and earn a dollar for every head, what is the expected value of this game? ii) If I can re-toss all 4 coins and must take the value from the second round, what is the expected value now? 4) How confident are you that you got 0, 1, 2, 3, or all questions correct, giving percentages? 5) If two teams play a best 4 out of 7 series, where each team has a 50% chance to win each round, what is the probability that the series lasts all 7 games?
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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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