Data Scientist Statistics & Math Interview Questions
Practice 471 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."
Compute precision under noisy annotators
This question evaluates understanding of statistical performance metrics and label-noise propagation by requiring computation of precision, recall, an...
Why is the t-statistic useful
This question evaluates understanding of the t-statistic and broader statistical inference competencies, focusing on interpreting effect size relative...
Compute probability match lasts 5 games
Two players play independent games of table tennis. - Player A wins each game with probability \(p\) (constant across games). - They play a best-of-5 ...
Use confusion matrix to choose model metric
This question evaluates understanding of confusion matrix components, mapping Type I/Type II errors to false positives/negatives, selection and interp...
Explain BLS vs CLS; compute t-stats
Part A — Concepts: Define Brand Lift Study (BLS) vs Conversion Lift Study (CLS) in ads measurement. List key bias/variance sources for each (e.g., non...
Compare Two Coin Proportions
You are given results from two independent coin-toss experiments: - Coin A was tossed 100 times and landed heads 40 times. - Coin B was tossed 1,000 t...
How do you derive CDF from a PDF?
This question evaluates understanding of the relationship between a probability density function and its cumulative distribution function, the formal ...
Compute decay, OLS, and classic probability results
You are asked several probability/statistics questions. 1) Radioactive decay (half-life) A radioactive atom has a half-life of 1 day. Assume each atom...
Compute credit-card portfolio profit and breakeven
A bank is evaluating a new credit card. Segments: A: 30,000 customers, capture rate 20%, avg annual spend per captured customer = $100,000. B: any pop...
Estimate population singletons from a 10% log
A daily search log has one row per query string. You draw a 10% simple random sample of rows without replacement. Define a “unique query” (singleton) ...
Infer causal impact without an A/B test
Evaluate Impact of a Shipped Version on Disconnections (No A/B Holdout) Context A new client version was shipped system-wide with the goal of reducing...
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 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...
Compute posterior for biased coin after 3H1T
You are given a coin known to be biased: one face lands with probability 2/3 and the other with probability 1/3, but you do not know whether Heads is ...
Estimate total attendance from size-biased reservation sample
You run a restaurant with N = 10,000 reservations in a day. Each reservation j has: - Reserved party size: \(R_j\) (positive integer) - Actual number ...
Calculate Expected Users Linking Coinbase Wallets
Expected Coinbase Wallet Linking When users sign up for Coinbase, each of the n users is independently prompted to link a crypto wallet. Each user lin...
Estimate unbiased ad scores with many reviewers
This question evaluates a candidate's skills in hierarchical and mixed-effects modeling, latent-variable estimation, debiasing rater severity and scal...
Compute P(third Ace | Ace in first two)
Conditional probability with cards drawn without replacement Problem You draw three cards without replacement from a standard 52‑card deck (4 Aces). G...
Compute A/B significance, CI, and power
You run an A/B test for 7 days. Control A: 520 conversions out of 10,000 sessions. Variant B: 630 conversions out of 11,500 sessions. Use a calculator...
Calculate Conversion Lift CI
This question evaluates statistical inference skills for proportions, specifically construction and interpretation of confidence intervals and hypothe...