JEE Main 2020MathematicsStatisticsEasyMCQ

JEE Main 2020 — Statistics Question with Solution

JEE Main 2020 (06 Sep Shift 1)

Question

If Σi=1nxi-a=n and Σi=1nxi-a2=na, n, a>1, then the standard deviation of n observations x1, x2, …,xn is
 

Choose an option

Show full solutionCorrect option: D
Correct answer
D(a-1)

Step-by-step explanation

SD, σ=∑xi2n-∑xin2

SD is independent of change of origin, so, for given data
σ=Σxi-a2n-Σxi-an2
=nan-nn2=a-1

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About this question

This is a previous-year question from JEE Main 2020, 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.