JEE Main 2024 · MathsMultiple choiceSingle correctEasyApplication

JEE Main 30 January 2024, Shift 2, Maths Q20

Question 20 of 90 in this shift, Maths question 20 of 30, Section A.

Bag A contains 3 white, 7 red balls and Bag B contains 3 white, 2 red balls. One bag is selected at random and a ball is drawn from it. The probability of drawing the ball from the bag A, if the ball drawn is white, is

(1) $1/4$
(2) $1/3$ Official answer
(3) $1/9$
(4) $3/10$

Official answer

Option 2

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 42 of the 174 JEE Main shifts held from 2017 to 2026.