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Solve complete questions with progressive hints, worked solutions and Python implementations. Each question explains its assumptions and source match. Original interpretations are labelled explicitly.

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Public standard problems and original exercises; hidden Trading Interview questions have not been verified.

174 titles have been investigated but remain unresolved. Their missing details are recorded without adding substitute exercises. Every playable question has a guided animated answer; selected questions also have custom diagrams.

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752 matching entries · page 1 of 16

Probability and Statistics · Medium

Kelly Betting #2

Original interpretation · Match confidence: medium

Company use unverified
About this question’s source match

The title and category identify this topic, but do not reveal the private statement. The explicitly specified scenario is an original, title-specific interpretation. Exact Trading Interview wording, numbers and requested subparts remain unverified; this is not claimed to be the hidden source question.

A hypothetical IID bet wins with probability 0.4 and pays net profit twice the stake; otherwise the entire stake is lost. You may stake fraction 0<=f<1 of wealth. Find log-optimal f, explain the general formula, and state the no-bet boundary.

Assumptions and constraints

  • Known fixed IID probabilities; net win 2 times stake; no fees or leverage.
  • Give exact expressions where possible and justify each requested result.

Examples

p 1/3,b 2
→ optimalf 0

The bet has no positive edge at these odds.

Company evidence · unverified

No company-specific source has been matched to this exercise. Its references support the topic or solution method; they do not establish employer use.

References

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Catalogue metadata captured 2026-10-12. Metadata source.