JEE Main 2021MathematicsStatisticsCalculation Of Standard Deviation Variance And Mean Deviation Of Grouped And Ungrouped DatamediumMCQ

JEE Main 2021 — Statistics Question with Solution

From: JEE Main 2021 (Online) 31st August Evening Shift

Question

The mean and variance of 7 observations are 8 and 16 respectively. If two observations are 6 and 8, then the variance of the remaining 5 observations is :

Choose an option

Show full solutionCorrect option: C
Correct answer
C

Step-by-step explanation

Let 8, 16, x1, x2, x3, x4, x5 be the observations.

Now,

.... (1)

Also,

..... (2)

So variance of x1, x2, ......., x5

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About this question

This is a previous-year question from JEE Main 2021, covering the Statistics 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.