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."
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"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."
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"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."
Analyze User Comment Distribution and Sampling Effects
Scenario You are analyzing daily comment counts per user. The per-user distribution of counts is right-skewed (many zeros/low counts and a long right ...
Compute A/B test sample size and Bayes posterior
You are working through two short, self-contained statistics tasks that appear together in an online assessment for a Data Scientist role. The tasks a...
Compare queueing systems and common distributions
Question You are asked a series of statistics fundamentals questions in a data science technical screen. 1. Queueing. A bank with 5 tellers can be org...
Compute multi-step Markov probabilities and estimate transitions
Problem (Markov Chain Probabilities) You are working with a discrete-time Markov chain over a finite set of states $S = \{s_1, \dots, s_n\}$. The chai...
Compute permutations with repeated letters
Counting Strings with Repeated Characters Problem Given two nonnegative integers m and n, how many distinct strings can be formed that contain exactly...
Design tests to verify shuffle randomness
Experiment Design: Is Your Array Shuffle Truly Random? You're given a shuffle(arr) function that takes an array of n distinct items and returns a rand...
Design human review to estimate model accuracy
You need to estimate the accuracy of an ML classifier on a population of subjects. You can only afford K total human reviews. Each human review produc...
Calculate Expected Users Adopting Wallet Feature
Wallet Feature Adoption – Probability and Expectation Setup - You are analyzing adoption of a new wallet feature. - There are N users. Each user indep...
Identify P-Value Limitations and Complementary Approaches
A/B Testing: Limits of P-values and Better Decision Practices Scenario Your team is running an A/B test for a new product feature and stakeholders rel...
Differentiate P-value and Confidence Interval in Statistics
Statistics Knowledge Check (Onsite Data Scientist) Task Explain core inferential statistics concepts and when to apply common hypothesis tests. Questi...
Determine Conditions for Multiplying Event Probabilities in Statistics
Scenario You are modeling multiple, distinct risk events in Coinbase Wallet (e.g., E1, E2, …, En) and want the probability that all occur, or that non...
Understand Simpson's Paradox with Simple Examples
Scenario You are a data scientist advising a product team on statistical analysis and experimental design. Tasks 1) Simpson’s paradox - Explain Simpso...
Calculate Probability of Heads in Coin Flip Experiment
Coin Flips: Counting and Binomial Probabilities Context Assume 10 independent flips of a fair coin (probability of heads p = 0.5 for each flip). Each ...
Calculate Posterior Fraud Probability Using Bayes' Theorem
Posterior Fraud Probability After a Flag Context You operate a fraud detection system that flags accounts as suspicious. Define: - F: account is fraud...
Compute answers to probability and counting puzzles
Below are several independent interview-style math/logic questions. 1) Barn legs You see only spiders, chickens, and cows in a barn. - Total legs = 56...
Generate Uniform Samples and Estimate Percentiles
Answer the following two probability/statistics questions. 1. You are given access to a function rand01() that returns independent samples from Unifor...
Compute Markov steady state and expectations
Probability and Game Theory: Three Sub-questions Context: The exact transition matrix P (for Q1) and the 2×2 payoff matrix (for Q3) are not provided. ...
Estimate percentile from buckets
You are given an approximate histogram of search-query frequencies. Each bucket i is represented as (left_bd_i, right_bd_i, bucket_count_i), where: - ...
Compute Bayes probability for fake accounts
A platform is trying to detect fake accounts. Assume: - Base rate of fake accounts is \(P(F)=p\). - A detection system flags an account as suspicious ...
Determine roles from B's accusation
Knights and Knaves: Single Statement Inference You meet two islanders, A and B. Each person is either a knight (always tells the truth) or a knave (al...