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."
Calculate Expected Draws for X > 0.8 in Uniform(0,1)
Scenario Quick probability check during a first-round screen to gauge statistical intuition. Question Let X ~ Uniform(0, 1). You draw independent samp...
Determine Probability of Friend Request Being Fake
Scenario You operate a platform where 95% of accounts are real and 5% are fake. Fake accounts send 10 times as many friend requests per account as rea...
Calculate Expected Flips for Heads-Tails Sequence
Probability Check — Waiting Time for HT Setup - You repeatedly flip a fair coin (independent flips; P(H)=P(T)=1/2). - Stop as soon as the consecutive ...
Choose Randomization Unit and Mitigate Network Effects
A/B Test Design for a New Messenger Feature with Network Effects Context You are designing an A/B test for a new Messenger feature in a social messagi...
How to Update Bayesian Model for Concept Drift?
Beta–Binomial CTR Model: Prior, Likelihood, Posterior, Smoothing, Intervals, and Drift Context You are discussing statistical foundations for a Bayesi...
Calculate Expected Comments and Confidence Interval Analysis
Scenario You are analyzing the distribution of comment counts per post for a social platform feature over a fixed time window. Let X be the random var...
Compute probability in urn with green returns
Urn Sampling with Replacement for Greens Only You have an urn with colored balls. You repeatedly draw one ball uniformly at random: - If the ball is g...
Explain Type I vs Type II errors
Prompt In hypothesis testing: 1. Define Type I error and Type II error. 2. Explain how they relate to significance level \(\alpha\) and power \(1-\bet...
Measure Causal Impact of Self-Selected App Redesign
Measuring Causal Impact of an Opt-in Mobile App Redesign Context A mobile app ships a redesigned UI as a new version. Users can choose to upgrade (opt...
Determine Superiority of Model A Using Hypothesis Testing
Scenario A search feature marks a user session as a success only if both the relevancy and accuracy binary flags equal 1. Two ranking models were A/B ...
Probability a negative review came from a lazy reviewer
Bayesian posterior: Did a negative review come from a lazy reviewer? Context and assumptions - Reviewer types in the population: - Lazy reviewers: 2...
Estimate Lift and Significance in Facebook Ad Campaigns
Measuring Conversion Lift from Facebook Ads Scenario An advertiser is running a randomized experiment on Facebook. Users are split into: - Control (un...
Explain P-value, Confidence Interval, and Multiple Testing Adjustments
A/B Testing and Inferential Statistics for a New Product Launch You are running online A/B experiments to evaluate a new product launch. Assume standa...
Compare Ad-Insertion Strategies: Expected Ads and Probabilities
Newsfeed Ad-Insertion Strategies You are evaluating two ways to insert ads into a user's newsfeed. Assume a user views a contiguous sequence of posts....
Calculate Probabilities for Mixed Reviewer Types
Scenario Two types of reviewers exist in a marketplace: - Lazy reviewers (20%) always give good reviews. - Careful reviewers (80%) give good reviews 6...
Model Unique Recipients with Poisson Distribution and Test Fit
Modeling Unique Recipients per Caller Scenario You need to model the distribution of the count of unique recipients each caller contacts in a fixed ti...
Analyze Distribution of Daily Page Shares Per User
Engagement Distributions and Cohort Dynamics You are analyzing per-user, per-day engagement. Assume a day-level panel with all users included (inactiv...
Estimate one-child household probability
You survey 100 children at a school and ask how many children are in their family. The responses are: - 50 children say their family has 1 child - 20 ...
Explain Type I/II errors vs precision/recall
Questions 1. Define Type I error and Type II error in hypothesis testing, and map them to false positives and false negatives. 2. Explain how Type I/I...
Combine noisy thermometers; compute random-walk correlations
Problem 1: Estimating a true temperature from noisy thermometers Assume the true (fixed) temperature is an unknown constant \(\theta\). 1a) One thermo...