JEE Main 2019MathematicsStatisticsCalculation Of Standard Deviation Variance And Mean Deviation Of Grouped And Ungrouped DatamediumMCQ

JEE Main 2019Statistics Question with Solution

From: JEE Main 2019 (Online) 9th April Morning Slot

Question

If the standard deviation of the numbers –1, 0, 1, k is where k > 0, then k is equal to

Choose an option

Show full solutionCorrect option: A
Correct answer
A2

Step-by-step explanation

standard deviation =

Variance = = 5

Also variance =

Where = Mean = =

Variance = -

5 = -

8 + 3k2 = 80

k2 = 24 = 2

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About this question

This is a previous-year question from JEE Main 2019, 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.