Medium · Probability & Combinatorics · Numerical · ~8 min · #49
HHT or HTT First?
Real interview · Jane Street
You flip a fair coin until either the pattern HHT or the pattern HTT appears. What is the probability that HHT appears first?
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Worked solution
Give the problem an honest attempt first, then reveal the full explanation.
Reported in interviews
- Jane StreetGlassdoor interview question
Candidate-reported and unverified; the firm may phrase it differently or no longer ask it. The wording here is our own paraphrase, and the solution was written and checked independently of any answers posted at the source.
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