Market Making Mental Math Interview Questions
Market making mental math interview questions for probability-to-price conversion, midpoint arithmetic, spread math, and quick quote checks.
Candidates who need faster quote arithmetic under pressure.
Quote math should be automatic
Market-making games move quickly. You need enough mental math fluency to compute fair values, spreads, and quote adjustments while still explaining reasoning.
Practice midpoint and spread
Given a midpoint and spread, compute bid and ask quickly. Given bid and ask, compute midpoint and spread just as quickly.
Concrete example
A 64 midpoint with a 6-point spread gives a 61 bid and 67 ask. If you skew down by 2, the quote might become 59 at 65.
Convert probabilities
Binary markets often convert probability directly to price. A 72 percent estimate maps to 72 on a 0-to-100 payoff scale.
Use approximation checks
Round when useful, then sanity-check whether the quote still sits on the correct side of fair value and risk constraints.
Common mistakes
Candidates sometimes optimize speed and lose sign discipline. Fast wrong quote arithmetic is worse than a slightly slower clean quote.
Practice the pattern
Use the LeetQuidity curriculum and calibration to turn this topic into a focused practice plan.