JEE Main 2021MathematicsProbabilityEasyNumerical

JEE Main 2021 — Probability Question with Solution

JEE Main 2021 (27 Aug Shift 2)

Question

The probability distribution of random variable X is given by:

X 1 2 3 4 5
P(X) K 2K 2K 3K K

Let p=P(1<X<4∣X<3). If 5p=λK, then λ is equal to

Enter your answer

Show full solutionCorrect answer: 30
Correct answer
30

Step-by-step explanation

ΣP(X)=1
⇒K+2K+2K+3K+K=1
K=19
P=P(1<X<4∣X<3)=P(X=2)P(X<3)
P=2K9KK9K+2k9K=23
5P=λK
5×23=λ×19⇒λ=30

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About this question

This is a previous-year question from JEE Main 2021, covering the Probability chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.