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About the test:

The Probability Test evaluates a candidate's understanding of probability concepts and their application in quantitative analysis. It assesses knowledge of topics such as quantitative aptitude, numerical reasoning, logical reasoning, and data interpretation, with a focus on probability theory.

Covered skills:

  • Probability Basics
  • Random Variables
  • Quantitative Aptitude
  • Combinatorics
  • Joint Distributions
  • Numerical Reasoning

9 reasons why
9 reasons why

Adaface Probability Assessment Test is the most accurate way to shortlist Data Analysts

Reason #1

Tests for on-the-job skills

The Probability Test helps recruiters and hiring managers identify qualified candidates from a pool of resumes, and helps in taking objective hiring decisions. It reduces the administrative overhead of interviewing too many candidates and saves time by filtering out unqualified candidates at the first step of the hiring process.

The test screens for the following skills that hiring managers look for in candidates:

  • Understanding of basic probability concepts
  • Ability to apply combinatorial techniques in probability problems
  • Knowledge of random variables and their properties
  • Understanding of joint probability distributions
  • Quantitative aptitude for solving probability-related problems
  • Ability to reason numerically in probability scenarios
Reason #2

No trick questions

no trick questions

Traditional assessment tools use trick questions and puzzles for the screening, which creates a lot of frustration among candidates about having to go through irrelevant screening assessments.

View sample questions

The main reason we started Adaface is that traditional pre-employment assessment platforms are not a fair way for companies to evaluate candidates. At Adaface, our mission is to help companies find great candidates by assessing on-the-job skills required for a role.

Why we started Adaface
Reason #3

Non-googleable questions

We have a very high focus on the quality of questions that test for on-the-job skills. Every question is non-googleable and we have a very high bar for the level of subject matter experts we onboard to create these questions. We have crawlers to check if any of the questions are leaked online. If/ when a question gets leaked, we get an alert. We change the question for you & let you know.

How we design questions

These are just a small sample from our library of 10,000+ questions. The actual questions on this Probability Test will be non-googleable.

🧐 Question


Green or red balls
A bag contains 5 red balls, 6 yellow balls and 3 green balls. If two balls are picked at random, what is the probability that both are red or both are green in colour?


Square points and Circle
What is the probability that two uniformly random points in the square are such that center of the square lies in the circle formed by taking the points as diameter


Increasing monthly gross profit
Percentage Calculations
The CEO of Snipr. Inc wants to grow monthly gross profit by 4%. If costs stay the same, what does the sales turnover need to be in February to achieve this goal?


Magic bag
Arithmetic Sequences
Alex’s uncle is a magician who gave them a magic bag in which coins get doubled each time you put those coins into it. Initially, Alex had few coins with them. So, Alex put all the coins, and the coins got doubled. Alex took out all the coins and gave a few to their friend and then again put the remaining coins back in the bag. The coins doubled again; Alex took out all the coins again and gave a few coins to their second friend. Alex then put the remaining coins in the bag and the coins doubled again. Alex took out all the coins and gave a few coins to their third friend. 
There were no coins left with Alex when Alex gave coins to the third friend and Alex gave an equal number of coins to each friend. What is the minimum number of coins Alex had initially and how much did Alex give to each friend?
A: Started with 3 coins
B: Started with 5 coins
C: Started with 6 coins
D: Started with 7 coins
E: Started with 9 coins
F: Gave 3 coins in every turn
G: Gave 4 coins in every turn
H: Gave 5 coins in every turn
I: Gave 7 coins in every turn
J: Gave 8 coins in every turn
K: Gave 9 coins in every turn


Three Clocks
Time Calculations
In my house, there are three clocks of different shapes – a round clock, a square clock, and a rhombus clock. The rhombus clock is always accurate whereas the round clock gains 2 minutes every day and the square clock loses 2 minutes every day. I checked the clocks on July 22nd, 2007 at 10 PM, and they were showing different times.
Two hours later, when I checked, the clocks were showing the same time, then on which date will all three clocks show the same time again?
A: 17 July 2008 
B: 23 Sep 2007
C: 25 July 2009
D: 19 Aug 2008
E: 26 July 2008
F: 28 Nov 2007
G: 11 June 2008
H: 15 Aug 2007
🧐 Question🔧 Skill


Green or red balls

2 mins



Square points and Circle

3 mins



Increasing monthly gross profit
Percentage Calculations

2 mins

Numerical Reasoning


Magic bag
Arithmetic Sequences

3 mins

Numerical Reasoning


Three Clocks
Time Calculations

3 mins

Numerical Reasoning
🧐 Question🔧 Skill💪 Difficulty⌛ Time
Green or red balls
Medium2 mins
Square points and Circle
Hard3 mins
Increasing monthly gross profit
Percentage Calculations
Numerical Reasoning
Medium2 mins
Magic bag
Arithmetic Sequences
Numerical Reasoning
Hard3 mins
Three Clocks
Time Calculations
Numerical Reasoning
Medium3 mins
Reason #4

1200+ customers in 75 countries

customers in 75 countries

With Adaface, we were able to optimise our initial screening process by upwards of 75%, freeing up precious time for both hiring managers and our talent acquisition team alike!

Brandon Lee, Head of People, Love, Bonito

Reason #5

Designed for elimination, not selection

The most important thing while implementing the pre-employment Probability Test in your hiring process is that it is an elimination tool, not a selection tool. In other words: you want to use the test to eliminate the candidates who do poorly on the test, not to select the candidates who come out at the top. While they are super valuable, pre-employment tests do not paint the entire picture of a candidate’s abilities, knowledge, and motivations. Multiple easy questions are more predictive of a candidate's ability than fewer hard questions. Harder questions are often "trick" based questions, which do not provide any meaningful signal about the candidate's skillset.

Science behind Adaface tests
Reason #6

1 click candidate invites

Email invites: You can send candidates an email invite to the Probability Test from your dashboard by entering their email address.

Public link: You can create a public link for each test that you can share with candidates.

API or integrations: You can invite candidates directly from your ATS by using our pre-built integrations with popular ATS systems or building a custom integration with your in-house ATS.

invite candidates
Reason #7

Detailed scorecards & benchmarks

View sample scorecard
Reason #8

High completion rate

Adaface tests are conversational, low-stress, and take just 25-40 mins to complete.

This is why Adaface has the highest test-completion rate (86%), which is more than 2x better than traditional assessments.

test completion rate
Reason #9

Advanced Proctoring

Learn more

About the Probability Online Test

Why you should use Pre-employment Probability Test?

The Probability Test makes use of scenario-based questions to test for on-the-job skills as opposed to theoretical knowledge, ensuring that candidates who do well on this screening test have the relavant skills. The questions are designed to covered following on-the-job aspects:

  • Understanding of Probability Basics
  • Knowledge of Combinatorics
  • Ability to work with Random Variables
  • Understanding of Joint Distributions
  • Quantitative Aptitude Skills
  • Numerical Reasoning Ability
  • Solid grasp of Probability Foundations
  • Proficient in Combinatorial Analysis
  • Advanced understanding of Random Variables
  • Expertise in Joint Probability Distributions

Once the test is sent to a candidate, the candidate receives a link in email to take the test. For each candidate, you will receive a detailed report with skills breakdown and benchmarks to shortlist the top candidates from your pool.

What topics are covered in the Probability Test?

  • Probability Basics

    The skill of Probability Basics involves understanding the fundamental principles and concepts related to probabilities, including calculating probabilities of events, using probability rules, and understanding the different types of probability distributions. This skill should be measured in the test to assess the candidate's foundational knowledge and understanding of probability, which is crucial in various fields such as statistics, data analysis, and decision making.

  • Combinatorics

    Combinatorics is the skill of counting and arranging objects or events. It encompasses concepts such as permutations, combinations, and the principles of counting. Measuring this skill in the test helps evaluate the candidate's ability to solve problems involving arranging, selecting, and counting objects, which is essential in various mathematical and statistical applications.

  • Random Variables

    The skill of Random Variables involves understanding the concept of random variables and their probability distributions. Random variables are variables whose values depend on the outcome of a random event. Measuring this skill in the test can assess the candidate's ability to analyze and interpret random phenomena, as well as apply probability distributions to model real-world situations.

  • Joint Distributions

    Joint Distributions refer to the probability distribution of two or more random variables. This skill involves understanding the joint probability distribution, conditional probability, and related concepts. Including this skill in the test helps evaluate the candidate's grasp on modeling and analyzing the relationships between multiple random variables, which is essential in various fields such as machine learning, finance, and operations research.

  • Quantitative Aptitude

    Quantitative Aptitude is the skill of solving mathematical problems and analyzing numerical data. It encompasses various mathematical concepts, including arithmetic, algebra, geometry, and graphs. Measuring this skill in the test allows recruiters to assess the candidate's ability to analyze and solve quantitative problems, which is valuable in roles that require data analysis, financial analysis, and problem-solving.

  • Numerical Reasoning

    Numerical Reasoning is the skill of understanding and applying logical and analytical reasoning to numerical information. It involves interpreting and analyzing numerical data, identifying patterns, and making logical deductions. Including this skill in the test helps evaluate the candidate's ability to analyze and draw conclusions from numerical information, which is important in roles that require critical thinking, problem-solving, and data interpretation.

  • Full list of covered topics

    The actual topics of the questions in the final test will depend on your job description and requirements. However, here's a list of topics you can expect the questions for Probability Test to be based on.

    Sample space
    Probability rules
    Conditional probability
    Independent and dependent events
    Permutations and combinations
    Factorial notation
    Probability distributions
    Expected values
    Mean, median, and mode
    Variance and standard deviation
    Binomial distribution
    Poisson distribution
    Normal distribution
    Central limit theorem
    Joint probability
    Marginal probability
    Conditional probability
    Random variables
    Probability density function
    Cumulative distribution function
    Expected value of a random variable
    Moment generating function
    Quantitative aptitude
    Number series
    Percentage calculations
    Data interpretation
    Quantitative comparison
    Numerical reasoning
    Probability puzzles
    Statistical analysis

What roles can I use the Probability Test for?

  • Data Analyst
  • Data Scientist
  • Business Analyst
  • Financial Analyst
  • Risk Analyst
  • Statistician
  • Market Research Analyst
  • Actuary
  • Operations Research Analyst
  • Quality Control Analyst

How is the Probability Test customized for senior candidates?

For intermediate/ experienced candidates, we customize the assessment questions to include advanced topics and increase the difficulty level of the questions. This might include adding questions on topics like

  • Analytical thinking and Quantitative Aptitude
  • Problem-solving skills in Numerical Reasoning
  • Strong grasp of Probability Concepts
  • Ability to apply Combinatorial Techniques
  • In-depth knowledge of Random Variable Models
  • Expertise in Joint Distribution Methods
  • Critical thinking and Quantitative Reasoning
  • Ability to analyze and interpret Numerical Data
  • Proficient in Probability Calculations
  • Skills in Combinatorial Problem-solving
  • Proficiency in working with Joint Probability Distributions
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The hiring managers felt that through the technical questions that they asked during the panel interviews, they were able to tell which candidates had better scores, and differentiated with those who did not score as well. They are highly satisfied with the quality of candidates shortlisted with the Adaface screening.

reduction in screening time

Probability Hiring Test FAQs

Can I combine multiple skills into one custom assessment?

Yes, absolutely. Custom assessments are set up based on your job description, and will include questions on all must-have skills you specify. Here's a quick guide on how you can request a custom test.

Do you have any anti-cheating or proctoring features in place?

We have the following anti-cheating features in place:

  • Non-googleable questions
  • IP proctoring
  • Screen proctoring
  • Web proctoring
  • Webcam proctoring
  • Plagiarism detection
  • Secure browser
  • Copy paste protection

Read more about the proctoring features.

How do I interpret test scores?

The primary thing to keep in mind is that an assessment is an elimination tool, not a selection tool. A skills assessment is optimized to help you eliminate candidates who are not technically qualified for the role, it is not optimized to help you find the best candidate for the role. So the ideal way to use an assessment is to decide a threshold score (typically 55%, we help you benchmark) and invite all candidates who score above the threshold for the next rounds of interview.

What experience level can I use this test for?

Each Adaface assessment is customized to your job description/ ideal candidate persona (our subject matter experts will pick the right questions for your assessment from our library of 10000+ questions). This assessment can be customized for any experience level.

Does every candidate get the same questions?

Yes, it makes it much easier for you to compare candidates. Options for MCQ questions and the order of questions are randomized. We have anti-cheating/ proctoring features in place. In our enterprise plan, we also have the option to create multiple versions of the same assessment with questions of similar difficulty levels.

I'm a candidate. Can I try a practice test?

No. Unfortunately, we do not support practice tests at the moment. However, you can use our sample questions for practice.

What is the cost of using this test?

You can check out our pricing plans.

Can I get a free trial?

Yes, you can sign up for free and preview this test.

I just moved to a paid plan. How can I request a custom assessment?

Here is a quick guide on how to request a custom assessment on Adaface.

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