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Probability and Statistics · Hard

Coefficient of Variation

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 positive waiting time X is exponential with mean 2 seconds. Compute CV=standard deviation/mean. Let Y=10X and Z=X+3 seconds; find both CVs. Explain the issue when a mean is zero.

Assumptions and constraints

  • Use the random mechanism explicitly specified in the prompt.
  • Give exact expressions where possible and justify each requested result.

Examples

X is always 2
→ CV=0

A deterministic value has no dispersion.

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.