150 Most Frequently Asked Questions On Quant Interviews |best| -
21. The Secretary Problem (Optimal Stopping): You have $N$ candidates. You see them one by one. How do you maximize the probability of picking the best candidate? 22. The Monty Hall Problem: Three doors, one car, two goats. You pick a door. The host opens another door revealing a goat. Do you switch? 23. Birthday Paradox: What is the probability that in a room of 23 people, at least two share a birthday? 24. Nim Game: Variations of the subtraction game where players remove objects from heaps. Determine the winning strategy. 25. Bayesian Inference: A rare disease affects 1 in 1,000 people. A test is 99% accurate. You test positive. What is the probability you actually have the disease?
What is Quantitative Easing (QE), and how does it alter market liquidity and asset prices compared to traditional open market operations?
How does the Feyman-Kac formula link partial differential equations (PDEs) to stochastic processes? Determine if the function is convex. Solve the first-order differential equation 150 Most Frequently Asked Questions On Quant Interviews
Questions frequently involve multi-stage games, imperfect testing scenarios, or signal processing where initial probabilities must be updated dynamically based on new evidence.
You pull a card from a deck and it's red. What is the probability that the next card is also red? How do you maximize the probability of picking
What is the Black-Scholes model, and what are its key assumptions? 4. Brainteasers and Logic Problems
such that the probability of at least two people sharing a birthday is greater than 50%? You pick a door
: You have two ropes. Each takes exactly 60 minutes to burn from end to end, but they burn unevenly. How do you measure exactly 45 minutes using these two ropes and a lighter?
“10 coins” puzzle (finding a counterfeit with a balance scale). Q85 - Q86: “100 prisoners” puzzle – optimization and strategy. Q87 - Q88: “Two ropes” – measuring 45 minutes using two ropes that each burn in 60 minutes but not uniformly. Q89 - Q90: “Ants on a stick” – collision problems. Q91 - Q92: “Blue‑eyed islanders” – logical deduction. Q93 - Q94: “The missing dollar” – accounting trick. Q95 - Q96: “Three doors” (Monty Hall). Q97 - Q98: “Circular table” – probability that a randomly placed leg leaves the table stable. Q99: “Heaven and Hell” (two doors, two guards) – logic puzzle. Q100 - Q101: “Poisoned wine” – information theory. Q102 - Q103: “Ball weighing puzzles” – optimal grouping strategies. Q104: “Two envelopes” – paradox. Q105 - Q106: “A bug walking along the edges of a triangle” – Markov chain and hitting probability. Q107: “Calendar cube” – forming all dates with two cubes. Q108: “Knight on a chessboard” – tour problems. Q109 - Q110: “Egg drop” – minimizing worst‑case drops.
Understand when to use Arrays, Linked Lists, Trees, Hash Maps, and Graphs.