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

JEE Main 2021Statistics Question with Solution

From: JEE Main 2021 (Online) 26th February Evening Shift

Question

Let X1, X2, ......., X18 be eighteen observations such
that and , where and are distinct real numbers. If the standard deviation of these observations is 1, then the value of | | is ____________.

Enter your answer

Show full solutionCorrect answer: 4
Correct answer
4

Step-by-step explanation

Given,



.... (1)

Also,



(using equation (1))



Given,















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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.