JEE Main 2021 · MathsMultiple choiceSingle correctEasyCalculation

JEE Main 3 August 2021, Shift 2, Maths Q78

Question 78 of 90 in this shift, Maths question 18 of 30, Section A.

A dice is thrown twice. If

A

is the event that the sum of numbers appearing on them is 7 and

B

is the event that number 5 appears at least once, then

P(B|A)

is equal to

(1) $\frac{1}{2}$
(2) $\frac{1}{3}$ Official answer
(3) $\frac{2}{11}$
(4) $\frac{2}{5}$

Official answer

Option 2

NTA final key.

Chapter: Probability
Topic: Conditional Probability
Idea tested: Reduced Sample Space Method

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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.