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 August Evening Shift

Question

Let the mean and variance of four numbers 3, 7, x and y(x > y) be 5 and 10 respectively. Then the mean of four numbers 3 + 2x, 7 + 2y, x + y and x y is ______________.

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Show full solutionCorrect answer: 12
Correct answer
12

Step-by-step explanation



Var(x) =





x + y = 10

(x, y) = (9, 1)

Four numbers are 21, 9, 10, 8

Mean = = 12

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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.