Easy · Probability & Combinatorics · Numerical · ~3 min · #113
Three Flips, at Least One Head
Real interview · Akuna Capital
I flip a fair coin three times and tell you that at least one flip was heads. What is the probability that I got exactly two heads and one tail?
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Worked solution
Give the problem an honest attempt first, then reveal the full explanation.
Reported in interviews
- Akuna CapitalGlassdoor interview question
We state explicitly that the information means at least one head.
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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