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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 · Easy

Kelly Betting #1

Original interpretation · Match confidence: medium

Susquehanna (SIG) · Topic guidance
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.

In a hypothetical repeated IID even-money bet, you win with probability 0.6 and lose with 0.4. Stake a fixed fraction f of current wealth, with 0<=f<1. Derive the fraction maximizing expected log wealth growth and compare with maximizing one-step expected wealth.

Assumptions and constraints

  • Known constant probabilities, IID repetitions, no fees; net win equals stake.
  • No leverage and wealth fraction less than 1.
  • Give exact expressions where possible and justify each requested result.

Examples

f 0
→ growth 0

Without a stake wealth does not change.

Company preparation relevance

These links connect this exercise to companies’ public examples or stated interview topics. They do not establish that a company asked this exact Learnr question.

  • Susquehanna (SIG)

    Official topic guidance

    Topic overlap: payoff decisions “Cash or Reroll”, stake-growth reasoning “Kelly Betting #1” and conditional probability “Liver Disease” practice probability, odds, expectancy and decision-making under uncertainty discussed on the firm’s trading-careers page.

    Susquehanna — Trading careers ↗
    Evidence scope and uncertainty

    Trading education and candidate puzzle culture. This page supports preparation relevance, not exact interview-question provenance.

    These are Learnr-authored exercises selected for topic overlap. The company does not name these catalogue titles or verify that these exact questions were asked.

References

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