Data Scientist Statistics & Math Interview Questions
Practice 455 real Statistics & Math interview questions for Data Scientist roles. From companies including Meta, Capital One, Google, Amazon, Uber.
"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."
Sketch function from derivatives and limits
Function analysis with derivative and concavity constraints Context (clarified): Assume f: R → R is differentiable everywhere and twice differentiable...
Derive expected meetings given nonempty room
Zero-Truncated Binomial: Random Room Assignment Setup - There are N rooms labeled 1, 2, ..., N. - K meetings are scheduled; each meeting independently...
Compute and correct correlation significance inflation
Sales Outreach Correlation Analysis: Inference, Multiple Testing, Power, and Simpson’s Paradox Context You are analyzing sales data to understand rela...
Choose and compute correct t-test
A/B Test: Watch Time per Impression (seconds) You ran an experiment with two independent groups and want to assess whether the new experience increase...
Interpret A/B results with p-values and uncertainty
A/B Test: Effect Sizes, CIs, Multiple Testing, Power, and Decision Context: You ran a 14‑day experiment (2025‑08‑15 → 2025‑08‑28) with 1:1 allocation ...
Compare average profit across mix scenarios
Burger Profit Mix — Scenario A vs. Scenario B Context: You sell two burger types (Regular and Vegan). In Scenario A, you sell only Regular. In Scenari...
Compute fraud probabilities with Bayes and Binomial
Fake-Account Detection with Binomial Sessions and Bayes Updating You are evaluating a rules-based detector for fake accounts on an online platform. Ea...
Estimate fake-account prevalence with capture-recapture
Capture–Recapture Estimation with Two Detectors You are evaluating suspected fake accounts on a platform with 50 million active accounts. In one week:...
Explain p‑values to a product manager
Interpreting a Two-Sided A/B Test p-value of 0.03 You ran a two-sided A/B test on conversion rate. Results: - Baseline (control) conversion: 5.0% - Ob...
Solve core probability/statistics mini-problems
Answer the following probability/statistics interview questions. Assume all randomness is independent unless stated otherwise. 1) Radioactive decay (h...
Compute expected counters after color elimination
Problem You have a bag with 30 counters: 10 red, 10 yellow, and 10 blue. You draw counters uniformly at random without replacement. Stop the moment th...
Write the logistic regression loss function
Logistic Regression Loss Consider binary logistic regression. - Dataset: \(\{(\mathbf{x}_i, y_i)\}_{i=1}^n\) - Labels: \(y_i \in \{0,1\}\) - Model: \(...
Explain and interpret p-values correctly
Context You are evaluating a change to a fraud decision rule (e.g., a new threshold or step-up authentication rule). You run an experiment comparing C...
Calculate Posterior Probability Using Bayes' Theorem Example
Bayes' Theorem: Spam-Flag Posterior You are evaluating a simple classifier that flags messages as spam. From historical data you know the spam prevale...
Calculate Annual Profit of Credit Card Portfolio
Portfolio Annual Profit Calculation Context You manage a portfolio of 500,000 active credit-card accounts. Each active card generates multiple revenue...
Explain Simpson’s Paradox and Its Causes with Example
Simpson’s Paradox: Definition, Cause, and Example Task You are asked to demonstrate your understanding of Simpson’s paradox in a statistics/analytics ...
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 ...
Determine Normality of Single Observation with Z-Test
Hypothesis Test for a Single Observation Against a Standard Normal Context You observe a single numeric value, x, and want to decide whether it could ...
Calculate Expected Day for First Selection in Sampling
Daily Sampling: First-Selection Day Context - There are 1,000 people. Each day, 10 distinct names are drawn uniformly at random. - We consider two reg...
Calculate Expected Meetings in Randomly Assigned Rooms
Random Assignment of Meetings to Rooms Scenario - There are N rooms and K meetings. Each meeting independently chooses a room uniformly at random (pro...