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) 20th July Evening Shift

Question

If the mean and variance of six observations 7, 10, 11, 15, a, b are 10 and , respectively, then the value of | a b | is equal to :

Choose an option

Show full solutionCorrect option: D
Correct answer
D1

Step-by-step explanation



a + b = 17 ..... (i)



a2 + b2 = 145 ...... (ii)

Solve (i) and (ii) a = 9, b = 8 or a = 8, b = 9

| a b | = 1

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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.