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."
Design rigorous A/B test and causal analysis
Experiment Design and Causal Inference: Multi-part Problem Context: You are designing a high-traffic web A/B test on a binary conversion metric. Answe...
Measure rider incentive causal ROI
Rider Incentive Targeting: Causal Incrementality, ROI, and Spillovers Context: You plan a rider‑side incentive (e.g., “20% off up to $10”) targeted by...
Validate DID and IV assumptions rigorously
Causal Inference and IV: DID, TWFE, Staggered Adoption, Clustering, and 2SLS Context: You are analyzing the causal effect of a reminder on an outcome ...
Calculate Year-1 profit margin
Year-1 Profit Margin Calculation Context You are assessing Year-1 profitability for a new vegan product line. Use the assumptions below (m = million) ...
Estimate constant under absolute loss
Suppose you have observed target values \(y_1, y_2, \dots, y_n\), and you want to fit the simplest possible model that predicts the same constant valu...
Analyze EV, arbitrage, and bet sizing across games
Betting Games: EV, Variance, Arbitrage, and Sizing Context You will be shown payout tables or odds for three independent games. Your task is to quickl...
Compute extinction probability in a branching process
You start with 1 cell at time 0. Every minute, each existing cell independently transitions with equal probability (1/4) into one of four outcomes: - ...
What are sum expectation and variance?
Let random variables X and Y have finite means and variances. How do you compute: 1. The expectation of X + Y 2. The variance of X + Y Your answer sho...
Compute monthly break-even subscribers
Break-even Analysis for a Subscription Streaming Service Context A streaming startup incurs monthly fixed costs and per-subscriber variable costs and ...
Compute Groupon unit economics and break-even
Restaurant Coupons and Unit Economics Context: A restaurant's variable cost (VC) is 40% of pre-discount spend and fixed cost (FC) is $100/day. Assume ...
Compute sample sizes and error control
Using the Biker experiment context, compute required sample sizes and describe error control under practical constraints. Show formulas and numeric an...
Price options and bonds via binomial no-arbitrage
Binomial No-Arbitrage Pricing: Options and Bonds Setup and Assumptions - Two-period models; per-period simple compounding. - Discount per period: (1 +...
Diagnose and interpret regression assumptions
OLS for Signups with Diagnostics and Alternatives You are given a cleaned dataset with the following columns: - signups: non-negative integer count ta...
Justify synthetic control and handle inference
Synthetic Control: Assumptions, Estimation, Inference, and Diagnostics Context You are estimating the causal effect of an intervention on a single tre...
Solve the 12-coin balance puzzle
The 12-Coin Counterfeit Puzzle (Three Weighings) You are given 12 visually identical coins. Exactly one of them is counterfeit. The counterfeit coin d...
Compute power and interpret uplift metrics
A/B Test on Conversion: Powering, Inference, CUPED, Multiple Testing, and Clustering You are running a two-arm A/B experiment on a binary conversion o...
Compute required output to recover 10% investment
Power Plant Profit Target and Capacity Feasibility Context You are evaluating a fossil-fuel power plant. The plant can sell all electricity it generat...
Quantify and Model Flight Delays Using Statistical Tests
Flight Delays: Quantification, Modeling, and Testing a Mitigation Strategy Scenario You are a data scientist investigating flight delays using histori...
Analyze distribution of a 3-dice product
You roll three independent fair 10-sided dice. Each die shows an integer in \(\{0,1,\dots,9\}\) with equal probability. Let the outcomes be \(X,Y,Z\),...
Compute ruin probability with bold betting
Probability of Reaching 5 Tokens Before Ruin Setup - You start with 3 tokens, target is 5 tokens, and ruin is 0. - On each turn, you bet as many token...