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."
Calculate Probability of Heads and Red Balls Drawing
Quick-Fire Probability (CodeSignal-style) Context: Answer the following independent probability questions, using binomial (independent trials) and hyp...
Compute probabilities for chatbot response quality
Context A chatbot response is considered good if it is both: - Helpful, and - Honest. You are told: - \(P(\text{Helpful}) = 0.8\) - \(P(\text{Honest})...
Compute probability at least one user uses feature
Problem Assume there are \(n\) users. Each user independently uses a certain feature with probability \(p\). 1) What is the probability that at least ...
Calculate Expected Users Linking Coinbase Wallets
Scenario When users sign up for Coinbase, each of the n users is independently prompted to link a crypto wallet. Each user links their wallet with pro...
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 \(X,Y,Z\),...
Solve probability and expectation problems
Probability and Statistics Mini-Set Context: Answer each item independently. Unless otherwise specified, assume independence and uniform randomness; d...
Match Netflix profit; derive required subscribers
Subscription Profit and Break-even (All Monthly) Assume all figures are monthly and "M" denotes millions. We model subscription profit as: - Profit = ...
Differentiate fixed and variable costs with examples
Unit Economics: Fixed vs. Variable Costs in a Subscription Streaming Business Task - Define fixed cost vs. variable cost for a subscription streaming ...
Compute precision under noisy annotators
Two-Annotator Labeling Policy: Precision, Recall, F1, and Generalization You have two independent annotators who review videos and label them as "ille...
Test a coefficient and explain t-distribution
In OLS, test whether feature j is relevant. a) State H0: β_j = 0 versus H1: β_j ≠ 0 and construct the t‑statistic t_j = b̂_j / se(b̂_j), giving the ex...
Define and sample a truncated normal
Define the truncated normal Z | a < Z < b for Z ~ N(0,1): write the normalized pdf and cdf. Then design efficient samplers for three cases: (i) a = 1,...
Compute robust linear interpolation with edge cases
You are given two distinct points (x0, y0) and (x1, y1) with x0 != x1. a) Derive the linear interpolation function f(x) on [min(x0, x1), max(x0, x1)] ...
Contrast OLS, DiD, and PSM assumptions
For the shuttle impact problem, contrast OLS, DiD, and PSM rigorously. Do the following: 1) write the OLS and two-way fixed-effects DiD regression equ...
Analyze ad targeting expectations and distributions
Ads Profit, Variance Decomposition, and Exponential Timing Context: You run an ad slot with two user segments. On each eligible page view (impression ...
Compute profit and decompose Groupon impact
You run a restaurant with these economics: baseline demand is 20 tables/day, average revenue is $30/table, variable cost (VC) is 40% of revenue, and f...
Optimize profitability for coding contract decisions
A client offers two mutually exclusive fixed-price projects starting 2025-10-01 with a hard deadline of 2025-10-31. Your current team has 3 engineers....
Interpret regression metrics and assumptions
A multiple linear regression is fit to predict arrival delay with standardized numeric predictors and one‑hot categorical variables. Without seeing th...
Compute A/B sample size under clustering
A/B Test Sample Size With Unequal Allocation, Clustering, and Attrition Context You are planning a two-arm signup A/B test (binary outcome: convert vs...
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...
Prove causality for trading metric drop
Goal You need to separate market-driven fluctuations from a product-caused decline in executed_trades per active user around a known release on 2025-0...