MediumStochastic Processes
How Long Until Ruin or Riches
OptiverSIG / Susquehanna
You start with 1 on a fair coin each round, stopping when you reach 100. What is the expected number of rounds until you stop?
Approach
Guess a quadratic in the starting stake and match the boundary conditions.
Answer
Show the final answer
The answer is 2100. Sign in free for the full worked solution and to check your own answer.
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