Probability Questions and Answers With Explanation - Wikitechy https://www.wikitechy.com/interview-questions/tag/probability-questions-and-answers-with-explanation/ Interview Questions Mon, 06 Sep 2021 06:39:15 +0000 en-US hourly 1 https://wordpress.org/?v=6.9 https://www.wikitechy.com/interview-questions/wp-content/uploads/2025/10/cropped-wikitechy-icon-32x32.png Probability Questions and Answers With Explanation - Wikitechy https://www.wikitechy.com/interview-questions/tag/probability-questions-and-answers-with-explanation/ 32 32 Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5 ? https://www.wikitechy.com/interview-questions/probability/tickets-numbered-1-to-20-are-mixed-up-and-then-a-ticket-is-drawn-at-random-what-is-the-probability-that-the-ticket-drawn-has-a-number-which-is-a-multiple-of-3-or-5/ https://www.wikitechy.com/interview-questions/probability/tickets-numbered-1-to-20-are-mixed-up-and-then-a-ticket-is-drawn-at-random-what-is-the-probability-that-the-ticket-drawn-has-a-number-which-is-a-multiple-of-3-or-5/#respond Wed, 18 Aug 2021 01:48:27 +0000 https://www.wikitechy.com/interview-questions/?p=2032

Tickets numbered 1 to 20 are mixed up and then a ticket is drawn at random. What is the probability that the ticket drawn has a number which is a multiple of 3 or 5 ?

A. 1/2

B. 2/5

C. 8/12

D. 9/20

Answer : D. 9/20…

Explanation:

Here, S = {1, 2, 3, 4, 19, 20}.
Let E = event of getting a multiple of 3 or 5
= {3, 6 , 9, 12, 15, 18, 5, 10, 20}.
P(E) = n(E) / n(S)
= 9/20

]]> https://www.wikitechy.com/interview-questions/probability/tickets-numbered-1-to-20-are-mixed-up-and-then-a-ticket-is-drawn-at-random-what-is-the-probability-that-the-ticket-drawn-has-a-number-which-is-a-multiple-of-3-or-5/feed/ 0 In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green ? https://www.wikitechy.com/interview-questions/probability/in-a-box-there-are-8-red-7-blue-and-6-green-balls-one-ball-is-picked-up-randomly-what-is-the-probability-that-it-is-neither-red-nor-green/ https://www.wikitechy.com/interview-questions/probability/in-a-box-there-are-8-red-7-blue-and-6-green-balls-one-ball-is-picked-up-randomly-what-is-the-probability-that-it-is-neither-red-nor-green/#respond Wed, 18 Aug 2021 01:43:40 +0000 https://www.wikitechy.com/interview-questions/?p=2029

In a box, there are 8 red, 7 blue and 6 green balls. One ball is picked up randomly. What is the probability that it is neither red nor green ?

A. 1/3

B. 3/4

C. 7/19

D. 8/21

E. 9/21

Answer : A. 1/3

Explanation:

Total number of balls = (8 + 7 + 6) = 21.
Let E = event that the ball drawn is neither red nor green
= event that the ball drawn is blue.
n(E) = 7
P(E) = n(E)/n(S)
= 7/21
= 1/3

]]> https://www.wikitechy.com/interview-questions/probability/in-a-box-there-are-8-red-7-blue-and-6-green-balls-one-ball-is-picked-up-randomly-what-is-the-probability-that-it-is-neither-red-nor-green/feed/ 0 Two dice are rolled together. What is the probability of getting two numbers whose product is even ? https://www.wikitechy.com/interview-questions/probability/two-dice-are-rolled-together-what-is-the-probability-of-getting-two-numbers-whose-product-is-even/ https://www.wikitechy.com/interview-questions/probability/two-dice-are-rolled-together-what-is-the-probability-of-getting-two-numbers-whose-product-is-even/#respond Wed, 18 Aug 2021 01:41:27 +0000 https://www.wikitechy.com/interview-questions/?p=2028

Two dice are rolled together. What is the probability of getting two numbers whose product is even ?

A. 17/36

B. 1/3

C. 3/4

D. 11/25

Answer : C. 3/4

Explanation:

Total number of outcomes possible when a die is rolled = 6 (∵ any one face out of the 6 faces).
Hence, Total number of outcomes possible when two dice are rolled, n(S) = 6 × 6 = 36.
Let E = the event of getting two numbers whose product is even.
= {(1,2), (1,4), (1,6), (2,1), (2,2), (2,3), (2,4), (2,5), (2,6), (3,2), (3,4), (3,6), (4,1), (4,2), (4,3), (4,4), (4,5), (4,6), (5,2),(5,4), (5,6), (6,1), (6,2), (6,3), (6,4), (6,5), (6,6)}

Hence, n(E) = 27
P(E) = n(E) / n(S)
= 27/36
= 3/4

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