JEE Main 2024 · MathsMultiple choiceSingle correctEasyCalculation

JEE Main 4 April 2024, Shift 1, Maths Q19

Question 19 of 90 in this shift, Maths question 19 of 30, Section A.

Three urns A, B and C contain 7 red, 5 black; 5 red, 7 black and 6 red, 6 black balls, respectively. One of the urn is selected at random and a ball is drawn from it. If the ball drawn is black, then the probability that it is drawn from urn A is :

(1) $\frac{5}{16}$
(2) $\frac{4}{17}$
(3) $\frac{5}{18}$ Official answer
(4) $\frac{7}{18}$

Official answer

Option 3

NTA final key.

Chapter: Probability
Topic: Bayes' Theorem
Idea tested: Bayes' Theorem Application

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.