Statistics & Math Interview Questions
Practice 482 real Statistics & Math interview questions for 2026 — Statistics & Math interview questions gathered from actual interviews, with detailed solutions to guide your interview preparation. Covers companies like Meta, Capital One, Google, Amazon, and Optiver and roles such as Data Scientist, Quant/Trader, ML researcher, and Data Analyst. This collection is distinctive because problems range from applied inference
"I got asked a hardcore MCM DP question and I saw it on PracHub as well. Solved that question in 5 minutes. Without PracHub I doubt I could solve it in 5 hours. Though somehow didn't get hired, perhaps I guess I solved it too fast? /s"
"Believe me i'm a student here jn US. Recently interviewed for MSFT. They asked me exact question from PracHub. I saw it the night before and ignored it cause why waste time on random sites. I legit wanna go back and redo this whole thing if I had chance. Not saying will work for everyone but there is certainly some merit to that website. And i'm gonna use it in future prep from now on like lc tagged"
"10 years of experience but never worked at a top company. PracHub's senior-level questions helped me break into FAANG at 35. Age is just a number."
"I was skeptical about the 'real questions' claim, so I put it to the test. I searched for the exact question I got grilled on at my last Meta onsite... and it was right there. Word for word."
"Got a Google recruiter call on Monday, interview on Friday. Crammed PracHub for 4 days. Passed every round. This platform is a miracle worker."
"I've used LC, Glassdoor, and random Discords. Nothing comes close to the accuracy here. The questions are actually current — that's what got me. Felt like I had a cheat sheet during the interview."
"The solution quality is insane. It covers approach, edge cases, time complexity, follow-ups. Nothing else comes close."
"Legit the only resource you need. TC went from 180k -> 350k. Just memorize the top 50 for your target company and you're golden."
"PracHub Premium for one month cost me the price of two coffees a week. It landed me a $280K+ starting offer."
"Literally just signed a $600k offer. I only had 2 weeks to prep, so I focused entirely on the company-tagged lists here. If you're targeting L5+, don't overthink it."
"Coaches and bootcamp prep courses cost around $200-300 but PracHub Premium is actually less than a Netflix subscription. And it landed me a $178K offer."
"I honestly don't know how you guys gather so many real interview questions. It's almost scary. I walked into my Amazon loop and recognized 3 out of 4 problems from your database."
"Discovered PracHub 10 days before my interview. By day 5, I stopped being nervous. By interview day, I was actually excited to show what I knew."
"I recently cleared Uber interviews (strong hire in the design round) and all the questions were present in prachub."
"The search is what sold me. I typed in a really niche DP problem I got asked last year and it actually came up, full breakdown and everything. These guys are clearly updating it constantly."
Explain Bias-Variance Trade-off Simply for Stakeholders
Scenario You are in a technical phone screen for a Data Scientist role. The interviewer asks you to communicate a core modeling concept in plain langu...
Calculate Expected Impressions and Probability for Users
Random Allocation of Y Ad Impressions to X Users Setup (assumptions) - There are X distinct users and Y ad impressions. - Each impression is assigned ...
Calculate Posterior Probability of Flagged User Being Bad Actor
Bayesian inference for abuse detection with error control Setup A platform runs a binary classifier that flags users who might be bad actors. Let: - p...
Determine Posterior Probability of Bad User Prediction
Evaluating a Classifier That Flags Bad Actors Question You are evaluating a binary classifier for detecting bad actors among users. Given: - Prevalenc...
Compute and estimate Markov transition probabilities
A system is modeled as a discrete-time Markov chain over m states S = {s1, s2, ..., sm}. Part A (multi-step probabilities): - You are given a row-stoc...
Explain a stochastic process simply
Question In plain, non-technical language, explain what a stochastic process is to a hiring manager. Include: - An intuitive definition (what varies, ...
Analyze Newton-Raphson Convergence, Choose Sigma, and Derive Vega
Context You are given the market price of a European option and must infer the Black–Scholes implied volatility. This requires solving for the volatil...
Solve coin probability and Bayesian inference problems
Coin-Flip Statistics: Pattern Racing, Runs, and Bayesian Updating You are given three independent questions about fair coin tossing and Bayesian updat...
How to compute correlation from variances
You have two random variables \(X\) and \(Y\). You are told: - \(\mathrm{Var}(X+Y)\) - \(\mathrm{Var}(X)\) 1) Is this information sufficient to determ...
Choose better bank queue and describe distributions
You are interviewing for a data role and are asked several probability/distribution questions. 1) Bank queue choice (queueing intuition) A bank has 5 ...
How do you detect and fix multicollinearity?
In a regression-style model (e.g., linear regression or logistic regression) you suspect multicollinearity among features. 1) What is multicollinearit...
Compute an A/B test p-value by hand
In an A/B test on a game feature, you measure conversion rate (binary outcome). - Control: n₁ = 1000 users, x₁ = 120 conversions - Treatment: n₂ = 980...
Compute expectations, conditionals, odds, and distributions
Fast Probability and Statistics (No Calculator) Context: Answer quickly with mental math and concise reasoning. Show set-up and any helpful shortcuts....
Calculate tiered cost and break-even
Tiered Pricing and Shipping Cost Function You are ordering q units from a vendor with the following pricing: - Fixed setup fee per order: $500 - Unit ...
Calculate Expected Streaks in Coin Toss Sequence
Expected Number of Streaks in Coin Tosses Scenario You toss a coin repeatedly. A "streak" (a run) begins on the first toss and whenever the current to...
Explain Statistical Concepts in A/B Testing and Corrections
A/B Testing: p-values, Power, and Error Rates with Multiple Comparisons Context You are reviewing the results of an online A/B experiment. Stakeholder...
Construct a 95% Confidence Interval for Comment Counts
Comment Activity Analysis: Mean CI, Sampling Distribution, and 95th Percentile Context You have a simple random sample of users with their comment cou...
Calculate Particle Survival Probability After Time t
Radioactive-Decay Style Probability Context You have 100 identical, independent particles. Each particle's lifetime is exponentially distributed with ...
Calculate Probability of Honest and Relevant Chatbot Answers
Chatbot Evaluation: Honesty and Relevance Scenario You are evaluating a customer-service chatbot. Define two events for any given answer: - H: the ans...
Determine Probability of Fourth Good Response After Three Successes
Evaluating Good-Response Rates for Chatbot Outputs Context You are evaluating chatbot/LLM responses. Treat each response as a Bernoulli trial (good vs...