A total of 1249 people registered for this skill test. Now, the probability that next 3 customers would order 2 egg sandwich is 3 * 0.7 * 0.7 *0.3 = 0.44. A) At least one 6, when 6 dice are rolled, B) At least 2 sixes when 12 dice are rolled, C) At least 3 sixes when 18 dice are rolled, Probability of ‘6’ turning up in a roll of dice is P(6) = (1/6) & P(6’) = (5/6). It looks like the answer to the question 21 is right (option A), but solution is wrong, since actual probabilities of events are P(A) = 0.402, P(B) = 0.296, and P(C) = 0.245, see explanation at https://github.com/arcadynovosyolov/math_and_prob/blob/master/note_on_question_21.ipynb. The probability of selling Egg sandwich is 0.7 & that of a chicken sandwich is 0.3. We can easily doing that by putting sample mean as 18 and population mean as 18 with σ = 6 and calculating Z. Q7 answer seems incorrect. Yes, we have removed 7 from score calculation. Let A be the event of passing in first test. 32) The inference using the frequentist approach will always yield the same result as the Bayesian approach. Therefore on integrating the given function from 0 to 6, we get 0.5276. I think all of them are Numerators. The probability that it would be Red in any spin is 18/38. This would yield in: Also note that since the roll of each dice are independent, the order of the outcomes matter i.e. Two fair dice are rolled. Thus the required probability is A/B which is 19/177. Therefore the probability is 19/59. What is the probability of getting all orange? I understand the idea, but if your objective is to test conditional probability maybe another example could be better. 3 Red & 1 white. Since it is mentioned that one of them is a girl, we can remove the BB option from the sample space. This way P(AUBUC) = P(A) + P(B) + P(C). 37) About 30% of human twins are identical, and the rest are fraternal. This means that we must choose 2 types from the remaining 12. Since all the pairs are independent of each other, the probability that all the offsprings are not red would be (0.75). This is the place where you’ll take your career to the next level – that of probability, conditional probability, Bayesian probability, and probability … - kojino/120-Data-Science-Interview-Questions. 2) In question 19 range of test scores is 18 to 24 and in the explanation you have explained for range 20 to 26 The first roll of the die is independent of the second roll. You play five games and always bet on red slots. This means that out of the 5 cards in your hand, three are the same type (Queen, Ace, 10, etc.) The relationship of machine learning with data science. We multiply these outcomes and get the answer. Should I become a data scientist (or a business analyst)? (and their Resources), 40 Questions to test a Data Scientist on Clustering Techniques (Skill test Solution), 45 Questions to test a data scientist on basics of Deep Learning (along with solution), Commonly used Machine Learning Algorithms (with Python and R Codes), 40 Questions to test a data scientist on Machine Learning [Solution: SkillPower – Machine Learning, DataFest 2017], Introductory guide on Linear Programming for (aspiring) data scientists, 6 Easy Steps to Learn Naive Bayes Algorithm with codes in Python and R, How to Download, Install and Use Nvidia GPU for Training Deep Neural Networks by TensorFlow on Windows Seamlessly, 16 Key Questions You Should Answer Before Transitioning into Data Science. Thus, the probability of people having a different birthday would be 364/365. Finding the probability of all 50 people having all different birthdays are as follows: Therefore, the probability of at least two people having the same birthday is the compliment of above, which is approximately 97%. Obviously, this article does not intend to be the end all be all for practice, but rather aims to be an assistant in quizzing your familiarity with some typical types of probability questions. =P(testing +ve and having typhoid) / P(testing positive). 34) The students of a particular class were given two tests for evaluation. A total of 1249 people registered for this skill test. What is the probability that exactly 2 of them will be boys? E(X) = P(grand prize)*(10405-5)+P(small)(100-5)+P(losing)*(-5). Check out the comprehensive ‘Ace Data Science Interviews‘ course which encompasses hundreds of questions like these along with plenty of videos, support and resources. 39) Jack is having two coins in his hand. (adsbygoogle = window.adsbygoogle || []).push({}); C) It doesn’t matter probability of winning or losing is the same with or without revealing one door, A) You should guess heads again since the tails has already occurred thrice and its more likely for heads to occur now, B) You should say tails because guessing heads is not making you win, C) You have the same probability of winning in guessing either, hence whatever you guess there is just a 50-50 chance of winning or losing, A) We would expect more number of 10 year-olds to be shorter than 55 inches than the number of them who are taller than 55 inches, B) Roughly 95% of 10 year-olds are between 37 and 73 inches tall, This article is quite old and you might not get a prompt response from the author. for a detailed discussion of the Monty Hall’s Problem. For the second pull, the probability of pulling the second orange marble is 2/11. Don’t Learn Machine Learning. 9) A fair six-sided die is rolled 6 times. If the yellow region is a 1 inch square and the outside square is of 2 inches. What is the probability that all 4 cards chosen by Anita are in the set of 8 cards chosen by Babita? The cases considered are for exactly 1, 2 and 3 sixes respectively. To be sure, the doctor wants to conduct the test. Answers to 120 commonly asked data science interview questions. What is the expected number of tosses to get the first heads? The probability value greater than 1. Now we cross-fertilize five pairs of red and white flowers and produce five offspring. Now, you are playing the game 5 times and all the games are independent of each other. If we roll one die, each outcome (the numbers 1 through 6) all have an equal probability of 1/6. Below are the distribution scores, they will help you evaluate your performance. There are 2 variants of this question: For anyone taking first steps in data science, Probability is a must know concept. Best of luck on the interview process and keep excelling. Hence, we need to remove the scenario of getting the letter right. I believe the correct answer to 7 is B not A. All partitions are equally likely. 36) Heights of 10 year-olds, regardless of gender, closely follow a normal distribution with mean 55 inches and standard deviation 6 inches. 27) Ahmed is playing a lottery game where he must pick 2 numbers from 0 to 9 followed by an English alphabet (from 26-letters). Samsung’s SBCs take up 40% of the market, Panasonic’s SBCs take up 25% of the market, and LG’s SBCs take up the rest. The US military tests its recruits for HIV when they are recruited. 3) In the explanation of question number 40 I think ‘since the probabilities are continuous, the probabilities form a distribution function ‘ is correct it shoud be P(AꓵCc) will be P(A-C), If AꓵC =Φ,then the explanation”P(AꓵCc) will be only P(A).”must be right.. As we can see from above, we have 6 possible outcomes where the sum is 4 or less. 1% of all Samsung and Panasonic’s SBCs are defective, whereas 2% of all LG SBCs are defective. Calculate the percentage of students who passed the second test given that they were also able to pass the first test. 19) Some test scores follow a normal distribution with a mean of 18 and a standard deviation of 6. You can assume that there are an equal number of males and females in the world. For the first question, we want to find the probability of marbles pulled in the order of blue, orange, and red. Thanks for publishing this set of problems. If you have any questions or doubts feel free to post them below. There are two companies manufacturing electronic chip. Now from here, there are two ways to solve the problem. What is the probability that 4 out of the 6 randomly selected patients recover? The choice C.) is incorrect since 0.7*0.3*0.7 and 0.3*0.7*0.7 have to be considered as well. 22) Suppose you were interviewed for a technical role. If in our hand, we have 3 queens, then that is 3 of the 4 suits from 1 of the 13 types. The probability that the female survives the year is .999592. 5) Consider a tetrahedral die and roll it twice. For all the outcomes to be unique, we have 6 choices for the first turn, 5 for the second turn, 4 for the third turn and so on, Therefore the probability if getting all unique outcomes will be equal to 0.01543. P(small) = 1/26-1/2600, the reason we need to do this is we need to exclude the case where he gets the letter right and also the numbers rights. You would need to know that, P(CcꓵA|A) = P(CcꓵAꓵA)/P(A) = P(CcꓵA)/P(A), Multiplying the three we would get – P(AꓵBꓵCc), hence the equations holds true. This is however not true. The frequentist Approach is highly dependent on how we define the hypothesis while Bayesian approach helps us update our prior beliefs. Illustration by author. Q7 – The answer A) can not be the correct one since it is > 1 (see Q6 ? (1,2) is a different result from (2,1), and so on. When you reveal that the first is a girl, you are revealing GX or XG and excluding BB and BX so that 2/4 remain.