JEE Main 2020 · MathsMultiple choiceSingle correctEasyApplication

JEE Main 8 January 2020, Shift 2, Maths Q69

Question 69 of 75 in this shift, Maths question 19 of 25, Section A.

Let A and B be two events such that the probability that exactly one of them occurs is

\frac{2}{5}

and the probability that A or B occurs is

\frac{1}{2}

, then the probability of both of them occur together is :

(1) $0.01$
(2) $0.02$
(3) $0.10$ Official answer
(4) $0.20$

Official answer

Option 3

NTA final key (Jan 2020).

Chapter: Probability
Topic: Conditional Probability
Idea tested: Conditional Prob via Venn Diagrams

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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.