JEE Main 2016MathematicsStatisticsEasyMCQ

JEE Main 2016Statistics Question with Solution

JEE Main 2016 (03 Apr)

Question

If the standard deviation of the numbers 2, 3, a and 11 is 3.5, then which of the following is true ?

Choose an option

Show full solutionCorrect option: D
Correct answer
D3a2-32a+84=0.

Step-by-step explanation

x x2
2 4
3 9
a a2
11 121
Sum16+a Sum134+a2


σ=x24-xi42

134+a24-16+a42=3510

12134+a2-16+a24=72

536+4a2-256-a2-32a=14

280+3a2-32a=196

3a2-32a+84=0.

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About this question

This is a previous-year question from JEE Main 2016, 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.