JEE Main 2021 — Probability Question with Solution
From: JEE Main 2021 (Online) 1st September Evening Shift
Question
Let X be a random variable with distribution.
If the mean of X is 2.3 and variance of X is 2, then 100 2 is equal to :
| x | 2 | 1 | 3 | 4 | 6 |
|---|---|---|---|---|---|
| P(X = x) | a | b |
If the mean of X is 2.3 and variance of X is 2, then 100 2 is equal to :
Enter your answer
Show full solutionCorrect answer: 781
Correct answer
781
Step-by-step explanation
| x | 2 | 1 | 3 | 4 | 6 |
|---|---|---|---|---|---|
| P(X = x) | a | b |
= 2.3
a + 6b = ..... (1)
.... (2)
From equation (1) and (2)
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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.