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

JEE Main 2021Statistics Question with Solution

From: JEE Main 2021 (Online) 16th March Morning Shift

Question

Consider three observations a, b, and c such that b = a + c. If the standard deviation of a + 2, b + 2, c + 2 is d, then which of the following is true?

Choose an option

Show full solutionCorrect option: B
Correct answer
Bb2 = 3(a2 + c2) 9d2

Step-by-step explanation

For a, b, c

mean =



We know, S.D. of a + 2, b + 2, c + 2 = S.D. of a, b, c = d



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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.