Quant interview preparation
The problems trading firms ask, taught by technique.
673 problems and 132 variations in probability, expectation, random processes, statistics, games and brainteasers. Every one has a complete worked solution, grouped by the idea that cracks it.
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HHT Before HTT
A fair coin is flipped repeatedly until either the pattern or the pattern has appeared as a run of three consecutive flips. Find the probability that appears first.
Learn the technique
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Solve, then check
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Read the solution
Complete, compact reasoning, with variations that twist the same idea.
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