JEE Main 2022 · MathsMultiple choiceTwo statementsMediumCalculation

JEE Main 28 July 2022, Shift 2, Maths Q79

Question 79 of 90 in this shift, Maths question 19 of 30, Section A.

Let A and B be two events such that

P(B|A)=\frac{2}{5},\ P(A|B)=\frac{1}{7}

and

P(A\cap B)=\frac{1}{9}

. Consider (S1)

P(A'\cup B)=\frac{5}{6}

, (S2)

P(A'\cap B')=\frac{1}{18}

Then

(1)Both (S1) and (S2) are trueOfficial answer
(2)Both (S1) and (S2) are false
(3)Only (S1) is true
(4)Only (S2) is true

Official answer

Option 1

NTA final key.

Chapter: Probability
Topic: Conditional Probability
Idea tested: Conditional Probability with De Morgan's Laws

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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.