QuantPrep

AI quant interview prep that actually explains your mistakes.

400+ probability, brainteaser, and stochastic-calculus problems. Adaptive selection. Live AI explanations. Built for candidates preparing for SIG, Optiver, Jane Street, Citadel Securities, IMC, Flow Traders, Akuna.

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#042 · optimal_stoppingdifficulty 4

In the classical secretary problem, as n → ∞, what fraction should you reject outright before accepting the next best-so-far candidate?

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FAQ

How is this different from QuantGuide, Tradermath, or OpenQuant?

Those are static question banks. You answer, see a solution, move on. QuantPrep adapts question selection to your weak spots, and every solution has a live AI rewrite that explains the same idea in a way you might actually click with. The same problem gets explained three different ways if you need.

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The canonical solution is one person's mental model of a problem. If it doesn't land for you, you're stuck. The AI generates an alternative — often more visual, often more intuitive — which is especially useful for stochastic and combinatorial problems where multiple valid framings exist.

What firms does this cover?

The question bank is sourced from the canonical quant-interview corpus — the same problem families that show up at the firms listed above and most others. Firm-specific mock tests are next on the roadmap.

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