CBSE Class 12 Mathematics Probability Q #827
KNOWLEDGE BASED
UNDERSTAND
1 Marks 2023 MCQ SINGLE
If for any two events A and B, P(A)=4/5 and P(A ∩ B)=7/10, then P(B/A) is equal to
(A) 1/10
(B) 1/8
(C) 7/8
(D) 17/20
Prev Next

AI Tutor Explanation

Powered by Gemini

Step-by-Step Solution

We are given P(A) = 4/5 and P(A ∩ B) = 7/10.

We need to find P(B/A), which is the conditional probability of B given A.

The formula for conditional probability is: P(B/A) = P(A ∩ B) / P(A)

Substituting the given values, we get: P(B/A) = (7/10) / (4/5)

P(B/A) = (7/10) * (5/4) = 35/40 = 7/8

Correct Answer: 7/8

AI Suggestion: Option C

AI generated content. Review strictly for academic accuracy.

Pedagogical Audit
Bloom's Analysis: This is an UNDERSTAND question because it requires the student to recall and apply the formula for conditional probability.
Knowledge Dimension: CONCEPTUAL
Justification: The question tests the understanding of the concept of conditional probability and its formula.
Syllabus Audit: In the context of CBSE Class 12, this is classified as KNOWLEDGE. The question directly tests a formula from the textbook.

More from this Chapter

VSA
What is the probability that a customer after availing the loan will default on the loan repayment?
SA
31. From a lot of 30 bulbs which include 6 defective bulbs, a sample of 2 bulbs is drawn at random one by one with replacement. Find the probability distribution of the number of defective bulbs and hence find the mean number of defective bulbs.
SA
For the vacancy advertised in the newspaper, 3000 candidates submitted their applications. From the data it was revealed that two third of the total applicants were females and other were males. The selection for the job was done through a written test. The performance of the applicants indicates that the probability of a male getting a distinction in written test is 0.4 and that a female getting a distinction is 0.35. Find the probability that the candidate chosen at random will have a distinction in the written test.
LA
(a) In answering a question on a multiple choice test, a student either knows the answer or guesses. Let 3/5 be the probability that he knows the answer and 2/5 be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability 1/3. What is the probability that the student knows the answer, given that he answered it correctly? OR (b) A box contains 10 tickets, 2 of which carry a prize of ₹8 each, 5 of which carry a prize of ₹4 each, and remaining 3 carry a prize of ₹2 each. If one ticket is drawn at random, find the mean value of the prize.
SA
The probability of simultaneous occurrence of at least one of the two events $X$ and$Y$ is $a$. If the probability that exactly one of the events $X, Y$ occurs is $b$, prove that $P(X') + P(Y') = 2 – 2a + b$.
View All Questions