Jane Street–styleTraderAssistant TraderQuestion #232

You repeatedly flip a fair coin until either the sequence HHT or HTT appears. If you can choose which combination to bet on (HHT or HTT), which should you pick and why? Calculate the probability of winning for each choice.

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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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