Maven Securities HackerRank Test Questions and Prep Notes

The Maven Securities HackerRank assessment is the kind of online assessment where speed matters as much as raw problem-solving ability. For a quant role, candidates should expect a blend of probability, logic, combinatorics, coding fundamentals, and practical data-processing thinking.

This guide rewrites a candidate-style Maven Securities HackerRank experience for ExtraBrain readers. It focuses on the question patterns, the likely reasoning skills behind them, and a responsible preparation workflow you can use before the assessment.

Use any AI interview assistant, including ExtraBrain, only where the interview, employer, school, workplace, and assessment platform rules allow AI assistance, transcription, screenshots, or notes. The safest use case is preparation, mock practice, post-practice review, and building better explanations before the real assessment.

Maven Securities HackerRank format at a glance

The reported assessment had two online rounds. Both rounds required the camera to be on, and the candidate noted that calculator use and scratch paper were not allowed.

The first round was a fast-paced multiple-choice section focused on math, probability, combinatorics, and logic. The second round had three LeetCode-style coding problems. The first round felt more time-pressured, while the coding round felt moderate but still required clean implementation.

For Maven Securities and similar quant firms, the assessment is not only checking whether you know algorithms. It is also checking whether you can reason accurately under time pressure, avoid careless probability mistakes, and translate a problem statement into code without overcomplicating it.

First-round Maven Securities HackerRank question patterns

The first round contained many short multiple-choice questions. The list below preserves the useful preparation value of the reported examples while framing them as practice prompts.

1. Knockout tournament games

There are 100 teams in a knockout competition. What is the least number of games required to decide the winner if no games are drawn?

Options: 50, 98, 99, 100, 101.

This tests the invariant that each game eliminates exactly one team. To leave one winner from 100 teams, 99 teams must be eliminated.

2. Random table legs on a circle

Three legs are placed uniformly at random around the circumference of a circular tabletop. What is the probability that the table can stand?

Options: 0, 1/4, 1/3, 1/2, 1.

This is a geometric probability question. The usual insight is to think about whether the three points all lie in some semicircle.

3. Last roll before reaching 100

A six-sided die is rolled and summed repeatedly until the sum is 100 or more. What is the most likely final roll?

Options: 1, 3, 4, 5, 6.

This tests renewal-style reasoning and overshoot intuition. It is easy to waste time if you try to simulate mentally, so practice recognizing the state-based structure.

4. Cookie box conditional probability

There are three cookie boxes. The first contains 20 chocolate cookies. The second contains 10 oat cookies. The third contains 5 chocolate, 5 oat, and 5 raspberry cookies. If two cookies are drawn from one randomly chosen box and both are chocolate, what is the probability they came from the first box?

Options: 1/2, 2/3, 41/46, 21/23, 10/11.

This is a Bayes rule question. The second box contributes zero probability, while the mixed box contributes a smaller but nonzero chance of drawing two chocolates.

5. First ace in a shuffled deck with jokers

A 54-card deck includes jokers. Cards are turned over one by one. What is the expected number of cards turned over before the first ace appears?

Options: 10, 10.5, 11, 13.5, 16.

This tests order statistics in a random permutation. A common shortcut is to treat the four aces as dividing the deck positions and use the expected minimum ace position.

6. Second-best player reaching the final

Eight players enter a knockout squash tournament. The first-round matchups are random, and stronger players always beat weaker players. What is the probability that the second-best player reaches the final?

Options: 3/8, 1/2, 4/7, 7/8, 1.

The second-best player only fails to make the final if placed in the same half of the bracket as the best player. This is a bracket-position probability problem.

7. Labeled dice summing to 16

There are 10 six-sided dice labeled from 1 to 10. How many different outcomes have face values that sum to 16?

Options: 3003, 5005, 8008, 8010, 11440.

This is a constrained integer composition problem. Because each die has values 1 through 6, you must account for both the lower bound and the upper bound.

8. Imperfect medical test

A disease affects 1% of the population. A test returns positive 99% of the time for someone with the disease and 5% of the time for someone without it. Given a positive test, what is the approximate probability the person actually has the disease?

Options: 17%, 20%, 84%, 98%, 99%.

This is another Bayes rule question. The base rate matters, and the false-positive population can dominate the true-positive population.

9. Arrangements of STATISTICS

How many unique arrangements are there of the letters in STATISTICS?

Options: 50400, 201600, 604800, 1814400, 3628800.

This is a permutation with repeated letters. Count the repeated letters carefully before applying the factorial formula.

10. Consecutive S letters in STATISTICS

For the word STATISTICS, what is the probability that all the S letters appear consecutively in a random arrangement?

Options: 1/40, 1/15, 2/15, 1/10, 1/5.

This is a grouping problem built on the previous repeated-letter arrangement count. Treat the block of S letters as one unit, then compare favorable arrangements to total arrangements.

11. Knight, liar, jester, and child logic puzzle

A knight always tells the truth, and a liar always lies. A jester tells the truth if the previous person lied and lies if the previous person told the truth. A child tells the truth after a truth and lies after a lie. Four people make statements about their identities. How many of the four statements are true?

Options: 0, 1, 2, 3, 4.

This is a consistency puzzle. The fastest approach is to assign possible roles and test the truth pattern rather than arguing from the story text informally.

12. Consecutive heads or tails

Jim flips a fair coin until he gets either two consecutive heads or two consecutive tails for the first time. What is the probability that he flips the coin an even number of times?

Options: 1/3, 1/2, 2/3, 4/7, 3/4.

This tests recursion or pattern reasoning. After the first flip, the process depends on whether the next flip matches or alternates.

13. Cereal-box coupon collector

There are 5 possible toys, and each cereal box contains one independently random toy. If each box costs £4, what is the expected cost to collect all 5 toys?

Options: £20, £45.68, £53.44, £58, £80.

This is the classic coupon collector problem. The expected number of boxes is 5 times the fifth harmonic number, then multiplied by the cost per box.

14. Divisibility among integers from 1 to 100

What is the smallest k such that any set of k distinct integers from 1 through 100 must contain two numbers where one divides the other?

Options: 49, 50, 51, 89, 100.

This is a pigeonhole principle problem. The useful trick is to group numbers by their odd part.

15. Three dice in strictly increasing order

Suyash rolls three dice. What is the probability that the values are in strictly increasing order?

Options: 9%, 56%, 33.3%, 25%, 17%.

This is a counting problem. Choose three distinct face values and then count how many orderings are strictly increasing.

16. Words built from O, MO, and LON

A language has only three syllables: O, MO, and LON. A word is any sequence of these syllables, with repetition allowed. How many different words of total length 5 can be formed?

Options: 7, 11, 12, 13, 16.

This is a recurrence or generating-function style problem. Let the syllable lengths be 1, 2, and 3, then count ordered compositions of total length 5.

17. Drawing balls from a large bag

A bag contains a large number of balls. One half are white, one third are red, and one sixth are blue. Given the first ball drawn is white, what is the approximate probability that the next ball is also white?

Options: 1/12, 1/6, 1/3, 1/2, 2/3.

Because the bag is described as containing a large number of balls, the probability is approximately unchanged by one draw. This tests whether you notice the approximation and avoid unnecessary finite-population calculations.

18. One selected integer is the average of the other two

Three different integers are randomly selected from 1 through 30. What is the probability that one of the numbers is the average of the other two?

Options: 1/30, 3/58, 13/290, 12/203, 3/116.

This is a combinatorics question about three-term arithmetic progressions. The middle number must be exactly halfway between the other two.

Second-round coding problems

The coding round was reported as three algorithmic problems. The problems were not described as extreme competitive-programming puzzles, but each one requires clean implementation and careful edge-case handling.

Problem 1: Maximum occurring character

The first coding task tested string traversal and character counting. The goal was to find the character that occurs most often. If multiple characters have the same count, the expected tie-break was to return the character that appears first in the input.

A reliable approach is to scan the string once, store counts in a hash map, and keep track of the earliest index for each character. Then choose the character with the highest count, breaking ties by smallest first index.

Key pitfalls include case sensitivity, whitespace handling if included in the input, and returning the lexicographically smallest character instead of the earliest occurring character.

Problem 2: Maximum array correlation

The second coding task tested greedy matching. The reported objective was to rearrange array b to maximize the number or value of positions where b[j] > a[j].

This resembles advantage-shuffle style problems. Sort both arrays, use the smallest b value that can beat the current a value when possible, and reserve weaker b values for positions that cannot be won.

The important reasoning skill is not the sorting itself. The important skill is explaining why using the smallest winning value preserves larger values for harder future comparisons.

Problem 3: Maximum distance

The third coding task tested multi-source breadth-first search and binary search. The reported idea was to compute the distance from each position to the nearest obstacle, then find a path that satisfies a distance constraint.

A common structure is:

1. Run multi-source BFS from all obstacle cells to compute nearest-obstacle distance for every cell.
2. Binary search the minimum allowed safety distance.
3. For each candidate distance, run a reachability check that only uses cells meeting the threshold.

This pattern appears in grid safety, path planning, and risk-aware routing problems. It rewards candidates who can separate preprocessing from feasibility checking.

What the assessment is really testing

Maven Securities quant assessments tend to reward speed, mathematical accuracy, and implementation discipline. Even if the exact questions change, the same skill clusters are likely to matter.

Probability and conditional reasoning

Several first-round prompts involve Bayes rule, expected value, geometric probability, or repeated random trials. Do not only memorize formulas. Practice identifying the sample space and writing the event you are conditioning on.

Combinatorics under time pressure

Repeated-letter permutations, dice sums, arithmetic progressions, and divisibility pigeonhole problems all appear in the reported set. These questions are often short, but they punish one-off counting errors.

Logic and invariants

The knockout tournament question is easy if you notice the elimination invariant. The knight-and-liar puzzle is easier if you write truth values systematically. In a timed setting, invariants often beat brute force.

Greedy algorithms

The array correlation task is a good example of a greedy matching problem. You need to know not only how to implement sorting and two pointers, but also why the greedy choice is safe.

Graph search and binary search

The maximum distance task combines BFS with binary search on an answer. That combination appears frequently when a problem asks for the largest possible minimum value or the safest feasible route.

A 10-day Maven Securities HackerRank preparation plan

If you have about 10 days, a focused schedule is better than a broad, anxious one. The goal is to improve your chance of solving cleanly under time pressure, not to learn every algorithm from scratch.

Days 1 and 2: Diagnose your baseline

Take one timed mixed quiz with probability, combinatorics, and logic questions. Then solve two easy-to-medium coding problems involving hash maps, sorting, and strings.

Use this stage to identify your weak points. If you consistently miss Bayes rule questions, schedule probability review early. If your code is slow to debug, spend time on implementation templates.

Days 3 through 7: Practice the highest-value patterns

Work through probability, combinatorics, arrays, hash maps, sorting, greedy algorithms, BFS, DFS, and binary search on answer. Keep the sessions short but timed.

A useful daily structure is:

• 60 minutes of math and logic practice.
• 90 minutes of coding practice.
• 30 minutes of reviewing mistakes.
• 20 minutes of writing short explanations for the problems you solved.

The explanation step matters because quant interviews often continue after the online assessment. Being able to explain your reasoning clearly is part of the signal.

Days 8 and 9: Run mocks

Take at least one timed mixed mock with no pausing. Simulate the real constraints as closely as allowed and practical. If the real assessment does not allow a calculator or scratch paper, practice mental setup and concise notation beforehand.

Review every mistake by category. Separate careless arithmetic errors from concept gaps and implementation bugs. Each category needs a different fix.

Day 10: Light review and mental readiness

Do not spend the final day trying to learn an unfamiliar advanced topic. Review formulas, common patterns, previous wrong answers, and implementation snippets you already understand.

Get enough sleep and prepare your assessment environment. A stable setup can matter as much as another hour of practice.

How ExtraBrain can fit into preparation

ExtraBrain is a free, local-first Mac desktop AI interview assistant and meeting copilot with live transcription, screen-aware context, local Gemma 4 where installed and compatible, bring-your-own AI providers, and privacy controls. For assessment preparation, it can help you review mock interviews, structure explanations, and keep a searchable record of your practice sessions.

ExtraBrain should be used only where rules allow. For many online assessments, that means using it before the real test for practice, not during a restricted assessment. Always follow employer, platform, school, and workplace policies.

Use ExtraBrain for mock debriefs

After a practice session, talk through the problems you missed and let ExtraBrain help organize the transcript into themes. For example, you might discover that your mistakes are mostly from rushed conditioning in probability questions rather than from lack of knowledge.

Use ExtraBrain to practice verbal explanations

For coding problems, do not stop at accepted code. Practice explaining the algorithm, complexity, edge cases, and proof idea out loud. ExtraBrain can help turn that live explanation into notes you can review later.

Use local-first settings when privacy matters

A fully local ExtraBrain posture requires local Parakeet transcription plus local Gemma 4 on-device AI where installed and compatible, with no external provider requests. If you choose external providers, selected prompts, transcript text, screenshots, audio, or context may leave the device depending on configuration.

Practical question-type checklist

Use this checklist before attempting Maven Securities-style HackerRank practice.

Area	What to practice	Why it matters
Probability	Bayes rule, expected value, dice, coin flips	Quant screens often test fast probabilistic reasoning
Combinatorics	Repeated permutations, integer sums, arithmetic progressions	Many MCQs are short counting traps
Logic	Truth-teller puzzles, invariants, pigeonhole principle	These reward structured reasoning under pressure
Strings	Frequency maps, tie-breaks, first occurrence tracking	Common easy coding tasks must be solved perfectly
Greedy	Sorting, two pointers, matching strategies	Medium coding tasks often require proof of optimal choice
Graphs	BFS, multi-source BFS, reachability	Grid and distance problems are common algorithmic screens
Binary search	Binary search on answer, feasibility checks	Helps solve maximize-the-minimum problems efficiently
Data processing	Parsing, aggregation, time-series basics	Quant roles often use coding to test practical data handling

Common mistakes to avoid

Do not spend too long on one multiple-choice question. If the setup is not moving after 60 to 90 seconds, mark it and continue.

Do not treat every coding problem as a dynamic programming problem. The reported set included counting, greedy matching, and BFS-style reasoning, which all have simpler direct approaches.

Do not ignore tie-break rules. The maximum occurring character problem is easy until you return the wrong character for equal frequencies.

Do not rely on partial correctness. For online coding assessments, full test-case coverage usually matters more than an elegant idea with buggy edge cases.

Do not use AI assistance in ways that violate assessment rules. Responsible preparation is different from unauthorized help during a proctored test.

FAQ

Does the Maven Securities HackerRank test require advanced finance formulas?

The reported experience did not emphasize complex professional finance formulas. It was closer to probability, statistics, algorithms, and practical data handling. Still, reviewing simple statistics such as mean, variance, covariance, and moving averages is sensible for quant preparation.

What should I prioritize if I cannot finish everything?

Prioritize fully correct solutions over many partial attempts. For coding rounds, passing all tests on two problems is often better than having several incomplete solutions. For multiple-choice rounds, move quickly but avoid blind guessing before you have eliminated obvious wrong answers.

How should I prepare for no calculator or scratch paper?

Practice setting up formulas mentally and simplifying before calculating. For combinatorics and probability, write practice solutions in a way that reduces arithmetic load. If scratch paper is not allowed in the actual assessment, your preparation should include mental structure drills.

Can ExtraBrain generate interview answers?

ExtraBrain can help generate answer outlines, STAR structures, technical explanations, and follow-up questions from live transcript and screen context. Candidates remain responsible for honest and allowed use.

What platforms does ExtraBrain support?

ExtraBrain is available for macOS today, including Apple Silicon and Intel Macs. Windows and Linux are planned future platforms.

Related practice guides

If you are preparing for quant or finance coding assessments, also practice questions from similar HackerRank-style screens. Useful adjacent topics include Citadel-style probability, Goldman Sachs coding assessments, JP Morgan software engineering screens, MathWorks algorithm assessments, and IBM HackerRank-style fundamentals.

For a broader interview workflow, use ExtraBrain to organize mock sessions, review transcripts, practice explanations, and build a focused interview preparation workspace.