JEE Main 2022MathematicsProbabilityEasyNumerical

JEE Main 2022 — Probability Question with Solution

JEE Main 2022 (29 Jul Shift 2)

Question

The sum and product of the mean and variance of a binomial distribution are 82.5 and 1350 respectively. They the number of trials in the binomial distribution is

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Show full solutionCorrect answer: 96
Correct answer
96

Step-by-step explanation

Given, sum of mean and variance is 82.5

Product of roots is 1350

Now, Mean and variance are the roots of 

x2-sum of rootsx+product of roots=0

⇒x2-82.5x+1350=0

⇒x=60 or 22.5

So, mean =np=60 and variance =npq=22.5

⇒ q=22.560=38

So, p=58 and n=6058=96

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About this question

This is a previous-year question from JEE Main 2022, 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.