Jane Street–styleTrader InternTrader InternQuestion #613
Walk me through the solution to the birthday problem (i.e., calculate the probability that at least two people in a group share the same birthday).
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State the assumptions, try a simple case, then work toward a general solution. Check the result and explain how it changes if an assumption changes.
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More Jane Street–Style Trader Intern Questions
In a group of 10 people standing in a circle, how many handshakes occur if each person shakes hands with every other person exactly once?Find the smallest positive integer x such that x raised to the power x (x^x) contains the digits '2016' consecutively. Determine a range [n, 2n] that contains this x. Additionally, specify how much you would bet on your choice and your level of confidence.How many throws of a fair 6-sided die are expected until each number appears at least twice?If copying, pasting, and typing a letter each take one second, what is the fastest way to reach at least 200 letters written?You roll a 4-sided die and sequentially accumulate the total score from each roll. What is the expected value of the first total that exceeds 100? Follow-up: What if you start at 96 instead of 0?
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