Intern Data Scientist Interview Questions
Data science internship interviews reward fundamentals over flash. These questions were reported by candidates interviewing for DS intern roles, so they cluster around what intern loops actually ask: probability and statistics, SQL queries, basic machine learning concepts, and lightweight, case-style problems that check whether you can reason about a metric or an experiment. The bar is approachable — interviewers know you don't have years of industry experience and listen for clear thinking and solid fundamentals rather than production ML. There are 40+ real, recently reported DS intern questions here across stats, SQL, ML, and case rounds, and most come with a worked solution so you can check your reasoning.
"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."
Evaluate Alternative Data for an Investment Pitch
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Count Distinct Island Shapes in a Binary Grid
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Quant Probability Brainteasers: Pizza Bounds, Coin Scores, Ant on a Cube, Shoelace Loops, and Paint Mixing
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Compute multi-step Markov probabilities and estimate transitions
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Handle multicollinearity in feature selection
You are building an interpretable predictive model for an insurance company, such as a linear or logistic regression model for claim risk. Several inp...
Count Same-Day Registered Posters
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Analyze Product Launch and Creator Engagement
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Implement and Tune KNN Classifier
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Find top-5 most similar rows across datasets
You can solve this in SQL or Python. You are given two datasets with the same feature columns: Tables target_rows (rows you want to match) - target_id...
Implement Univariate Linear Regression with Ordinary Least Squares
Implement univariate (simple) linear regression fitted in batch with the ordinary least squares (OLS) closed-form solution. You must implement the for...
Find kth missing integer and redundant operations
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Find top-5 most similar rows across datasets
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