Easy · Stochastic Processes & Markov Chains · Numerical · ~5 min · #62

One Dollar Against Two

Real interview · Susquehanna (SIG)

You have 1 dollar and your friend has 2. You repeatedly bet 1 dollar against each other until one of you is broke. You win each bet with probability $\tfrac23$ .

What is the probability that you end up with all 3 dollars?

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Worked solution

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Reported in interviews

Susquehanna (SIG)Glassdoor 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.

Concepts

Gambler's ruinFirst-step analysis

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