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Statistics & Math 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
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Showing 61–78 of 78 results
- SIG (Susquehanna)MediumQuantitative TraderExpected Payoff of a Three N-Sided Dice Matching Game
An expected value question about rolling three fair N-sided dice, with different payoffs when all three match, exactly two match, or all differ. It tests counting the outcome classes correctly for a general number of faces and combining them into one expected payoff, including a variant where the all-different outcome costs money.
Statistics & MathOnline Assessment - SIG (Susquehanna)EasyData ScientistFind Expected Spins Until Two Regions Appear
This problem tests knowledge of expected value and geometric distributions by calculating the expected number of trials to observe two distinct outcomes from a discrete probability distribution.
Statistics & MathOnline AssessmentProbabilityExpected ValueGeometric Distribution - SIG (Susquehanna)EasyData ScientistFind a Green Triangle's Weight in a Balanced Mobile
Solve a nested balanced-mobile puzzle and determine the green triangle's weight from a 160-pound total. The worked derivation uses an explicit equal-arm, massless-bar assumption, propagates whole-submobile weights upward, and explains why the left branch alone fixes the answer at 10 pounds.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumData ScientistFind probability of overlapping blooms
This question evaluates understanding of probability theory, specifically reasoning about continuous uniform distributions, geometric probability, and the likelihood of overlap between random time intervals within a fixed horizon.
Statistics & MathOnline Assessment - SIG (Susquehanna)EasyData ScientistFind the Expected Number of Consecutive Chosen Pairs
Calculate the expected number of consecutive pairs in a uniformly chosen subset of integers using indicator variables and linearity of expectation.
Statistics & MathOnline Assessmentprobabilitycombinatoricsexpected-value - SIG (Susquehanna)EasyData ScientistFind the Probability Two Muffins Are Sufficient
This problem tests binomial probability distributions and the cumulative probability of independent discrete events.
Statistics & MathOnline AssessmentProbabilityBinomial DistributionStatistics - SIG (Susquehanna)EasyData ScientistFind the Success Probability of Bold Betting
Calculate the chance of reaching five tokens before ruin under a bold, state-dependent betting rule. The solution enumerates the transitions, sets absorbing boundaries, solves the four-state recurrence for win probability one-third, and obtains 15/77 from an initial fortune of two.
Statistics & MathOnline Assessment - SIG (Susquehanna)EasyData ScientistInfer posterior after losing pick
This question evaluates a candidate's understanding of conditional probability and posterior inference, assessing the ability to update probability estimates after observing that a chosen option did not occur.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumQuantitative TraderProbability Limited Stock Covers Every Customer in a Queue
A binomial probability question about a queue of N customers who each choose one of two products, with only M units of one product left in stock. It asks for the probability that the stock is enough, or exactly enough, for every customer who wants it, testing distribution modeling and the efficient evaluation of tail sums.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumQuantitative TraderProbability Two Randomly Started Flower Bloom Periods Overlap
A probability question about two flowers that start blooming on random days within a D-day window and stay in bloom for different lengths of time. It asks for the probability that both are in bloom together at some point, testing interval-overlap reasoning, exact counting, and discrete versus continuous modeling.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumQuantitative TraderProbability You Picked the Strongest Cat Given Your Cat Lost the Race
A conditional probability puzzle about three cats in a race with known winning probabilities. You cheer for a randomly chosen cat, learn whether it won or lost, and must find the probability that you picked the strongest or the weakest cat, testing Bayes' rule and the choice of conditioning event.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumQuantitative TraderProbability of Reaching a Chip Target Under Bold Betting
A gambling probability question: starting with A chips and aiming for B, a player uses bold play, staking either all chips or just what is needed to reach the target, and wins each even-money round with probability p. It asks for the probability of reaching the target before going broke, testing recursive state analysis.
Statistics & MathOnline Assessment - SIG (Susquehanna)EasyData ScientistResolve Two Knights-and-Knaves Statements
This question tests logical deduction and systematic case analysis under binary truth constraints.
Statistics & MathOnline AssessmentLogicPuzzlesDiscrete Math - SIG (Susquehanna)EasyData ScientistSolve Barn Animal Counts from Total Legs
Tests setting up and solving a system of linear equations from verbal constraints using substitution to determine integer entity counts.
Statistics & MathOnline Assessmentmathalgebraquantitative-reasoning - SIG (Susquehanna)EasyData ScientistSolve animals-and-legs count
This question evaluates a candidate's ability to translate a word problem into a system of linear equations and perform basic algebraic manipulation and arithmetic to determine unknown quantities.
Statistics & MathOnline Assessment - SIG (Susquehanna)MediumData ScientistSolve relative-truth cat puzzle
This question evaluates logical deduction, constraint satisfaction, and quantitative manipulation of percentages and averages within a relative truth/lie framework, and is categorized under Statistics & Math and discrete logic puzzles.
Statistics & MathOnline Assessment - SIG (Susquehanna)EasyData ScientistUse Bayes for factory identification
This question evaluates understanding of Bayesian inference and conditional probability by asking for the posterior probability that two observed black widgets originated from a specific factory.
Statistics & MathOnline Assessment - WaymoMediumData ScientistAssess Routing Experiment Validity
This question evaluates experimental analysis and statistical hypothesis testing skills, including data preparation and joining, interpretation of p-values, and understanding of causal inference and threats to validity in A/B tests.
Statistics & MathOnline Assessment
SIG (Susquehanna)
Waymo