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Interview Questions
Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.
- 9403
- Questions
- 546
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- 11
- Topics
- 8
- Languages
Showing 1981–2010 of 9403 results
- Capital OneEasyData ScientistCalculate first-year profit margin
This question evaluates a data scientist's quantitative reasoning about unit economics and financial metrics, including understanding fixed versus variable costs and computing profit margin as a percentage.
Statistics & MathTechnical Screen - Capital OneEasyData ScientistCalculate profit and break-even across pricing models
This question evaluates understanding of unit economics, break-even analysis, and pricing-model effects on profitability by requiring computation of revenue, variable and fixed costs, and profit under per-GB and two-tier pricing scenarios.
Statistics & MathTechnical Screen - Capital OneMediumProduct ManagerCapital One Credit Card: Acquisition & Promotion Strategy
Practice a Capital One credit card acquisition and promotion strategy case for a mid-tier rewards card. The solution covers target segments, channel strategy, funnel goals, promotion trade-offs, sign-up bonus ROI, risk guardrails, payback logic, and metrics for profitable account growth.
Product / Decision MakingTechnical Screen - Capital OneMediumSoftware EngineerCard Issuer Backend: Fast Purchase Approvals and a Secure PII Vault
Design the issuer-side platform that approves or declines card purchases in tens of milliseconds, settles them later, and stores cardholder identity data so a breach of any one service exposes as little as possible.
System DesignTechnical Screensystem-designpaymentslatency - Capital OneHardData ScientistChallenge and validate assumptions
This question evaluates a data scientist's competency in identifying fragile business assumptions, conducting sensitivity analysis, and designing experiments and observational studies to validate parameters related to demand, price elasticity, cannibalization, supply constraints, labor learning curves, regional heterogeneity, and promotional decay.
Analytics & ExperimentationTechnical Screen - Capital OneMediumSoftware EngineerCheck Alternating Highs and Lows Around a Circular Array
Check strict high-low alternation around a circular array, including equal neighbors, wraparound comparisons, and the two-element case.
Coding & AlgorithmsOnline Assessment - Capital OneEasyData ScientistClean and Merge Housing Data
This question tests the ability to clean messy housing datasets, handle inconsistent data types, and perform efficient left-joins with external reference data.
Data Manipulation (SQL/Python)OnsitePandasData CleaningSQL - Capital OneMediumData ScientistCompare Logistic Regression and Random Forest in Python
Design, evaluate, and contrast a Logistic Regression baseline and a Random Forest model on an imbalanced credit default prediction dataset in Python. Walk through pipeline design, validation strategy, probability calibration, decision thresholding, and production trade-offs.
Machine LearningTechnical ScreenClassificationModel EvaluationPipelines - Capital OneMediumData AnalystCompare Two-Year Economics for Renewing or Replacing a Show
Calculate two-year show profits, derive the success-probability break-even point, and evaluate renewal and profit-improvement choices.
Analytics & ExperimentationTechnical Screen - Capital OneEasyData ScientistCompare average profit across mix scenarios
This question evaluates understanding of expected value, weighted averages, and profit-margin analysis within the Statistics & Math domain for a Data Scientist role. It is commonly asked to probe quantitative reasoning about pricing and cost trade-offs, and it tests practical application of arithmetic and scenario-based profit modeling rather than abstract theoretical concepts.
Statistics & MathTechnical Screen - Capital OneEasyData ScientistCompare average unit profit under mix shift
This question tests the candidate's ability to calculate weighted averages and understand how changes in sales volume distribution (mix shift) affect the overall average profit per unit.
Statistics & MathTechnical ScreenStatisticsWeighted AverageUnit Economics - Capital OneMediumData ScientistCompute Customer Spend and Engineer Features for 2023
This question evaluates proficiency in SQL-based temporal aggregation and Python feature engineering on transactional datasets, including computing monthly spend summaries and engineering category-level spending features.
Data Manipulation (SQL/Python)Onsite - Capital OneEasyData ScientistCompute Groupon unit economics and break-even
A Capital One data science technical screen case on restaurant unit economics with a Groupon-style voucher. You compute baseline daily profit from a 20-table day, derive the break-even check for a voucher table under a $30-for-$15 offer with a 40% commission, profit a mixed 25-table day, and decompose the profit change into traffic, check size and voucher cost. Full worked arithmetic, a sensitivity solve, and the incrementality follow-ups an interviewer expects.
Statistics & MathTechnical Screen - Capital OneEasyData ScientistCompute Optimal Die Re-roll Strategy
This question tests the ability to calculate expected values and determine optimal decision thresholds in a multi-stage probabilistic game.
Statistics & MathOnsiteProbabilityExpected ValueDecision Theory - Capital OneMediumData ScientistCompute and interpret 95% confidence intervals
This question evaluates proficiency with confidence intervals, hypothesis testing for proportions and means, multiple-comparison adjustment (Bonferroni), and sample size calculations, including assessment of normal-approximation versus Wilson score methods.
Statistics & MathOnline Assessment - Capital OneMediumData ScientistCompute capacity, staffing trade-offs, and break-even
This question tests the ability to model operational costs, evaluate staffing trade-offs between overtime and contracting, and perform break-even analysis under varying volume assumptions.
Analytics & ExperimentationHR ScreenCapacity PlanningCost AnalysisOperations - Capital OneMediumData ScientistCompute credit-card portfolio profit and breakeven
This question evaluates financial modeling, unit-economics calculation, breakeven analysis, and basic risk/expected-loss estimation relevant to a Data Scientist, testing competency in statistics & math and algebraic derivation within financial analysis.
Statistics & MathOnsite - Capital OneEasyData ScientistCompute current annual profit
This question evaluates numerical proficiency in financial arithmetic, unit-aware quantitative reasoning, and per-customer business-metric computation within a loyalty program context.
Statistics & MathTechnical Screen - Capital OneMediumData ScientistCompute expansion profits and expected value
This question evaluates financial modeling, expected-value decision-making, probability reasoning, and sensitivity analysis skills applied to revenue, variable and fixed cost interactions and contractual fee impacts, aimed at a Data Scientist role.
Statistics & MathOnsite - Capital OneEasyData ScientistCompute incremental profit, breakeven, and revenue sensitivity
A Capital One data scientist technical-screen case on cost accounting and profitability modeling. Candidates compute the Year-1 incremental profit of a new vegan burger line, decompose it into fixed versus variable components, derive breakeven volume, and run a ±10% sensitivity analysis.
Statistics & MathTechnical Screen - Capital OneHardMachine Learning EngineerCompute minutes since last train departure
This problem tests your ability to manipulate time objects, handle cyclic day-wrap scenarios, and perform efficient searching on sorted lists.
Coding & AlgorithmsOnline AssessmentArraysSortingTime Complexity - Capital OneMediumData ScientistCompute optimal stopping in a die-rolling game
This question evaluates a candidate's grasp of optimal stopping theory, expected value computation, and finite-horizon decision-making under uncertainty, including recognition of threshold-based policies and backward-induction reasoning relevant to data scientist roles.
Statistics & MathTechnical Screen - Capital OneMediumData ScientistCompute partnership profit and break-even population
This question evaluates competency in analytics and experiment-driven financial modeling, covering unit economics, cannibalization versus true lift, break-even and sensitivity analysis, and interpretation of segment-level impacts on partnership profitability.
Analytics & ExperimentationTechnical Screen - Capital OneMediumData ScientistCompute profit and break-even for memberships
This problem tests your ability to model unit economics for a subscription-based loyalty program and perform sensitivity analysis to determine the break-even point for a business intervention.
Statistics & MathTechnical ScreenEconomicsLinear ModelingBreak-even Analysis - Capital OneMediumData ScientistCompute required output to recover 10% investment
This question evaluates a candidate's ability to perform cost-volume-profit analysis and quantitative financial modeling, assessing skills in algebraic formulation of profit equations, capacity constraint evaluation, and derivation of generalized feasibility formulas.
Statistics & MathTechnical Screen - Capital OneMediumData ScientistCompute unit economics and insurance break-even
This question evaluates a candidate's proficiency in unit economics, insurance break-even analysis, expected-value modeling, churn effects, pricing versus demand trade-offs, and basic statistical inference including MLE and confidence intervals.
Statistics & MathTechnical Screen - Capital OneMediumData ScientistConsider Key Factors Before Launching New Credit Card
Evaluates launch-readiness analysis for a new consumer credit card across market, customer, risk, compliance, operations, and financial viability. Strong answers validate assumptions and define go/no-go criteria.
Behavioral & LeadershipHR Screen - Capital OneMediumSoftware EngineerCount Numbers With Odd Zeros
This question evaluates proficiency in numeric digit analysis and parity-based counting, testing the competency to reason about decimal representations of integers within the Coding & Algorithms domain at a practical application level. It is commonly asked to assess basic algorithmic thinking, efficient iteration and counting skills, and careful handling of edge cases in technical interviews.
Coding & AlgorithmsTechnical Screen - Capital OneMediumSoftware EngineerCount Pairs of Cyclically Equivalent Integers
This problem tests your ability to normalize strings under cyclic rotation using hashing or canonical representation, combined with frequency counting to efficiently identify equivalent pairs.
Coding & AlgorithmsOnline AssessmentHashingStringsCombinatorics - Capital OneMediumSoftware EngineerCount Pairs of Points Within 2 Units on Both Axes
A coding question that asks how many pairs of points intersect, where two points intersect when both their x-coordinates and their y-coordinates differ by at most 2. It tests counting unordered pairs with duplicate points, inclusive bounds and scaling to 100,000 points with large coordinates.
Coding & AlgorithmsOnline Assessment
Capital One