JEE Main 2017MathematicsStatisticsEasyMCQ

JEE Main 2017 — Statistics Question with Solution

JEE Main 2017 (09 Apr Online)

Question

The sum of 100 observations and the sum of their squares are  400 & 2475, respectively. Later on, three observations 3, 4 & 5 were found to be incorrect. If the incorrect observations are omitted, then the variance of the remaining observations is

Choose an option

Show full solutionCorrect option: C
Correct answer
C9.00

Step-by-step explanation

Given ∑i=110xi=400 and

∑i=1100xi2=2475

Variance of 97 observations=σ2=∑xi2N-∑xiN2    

∴ 3+4+5=12, 32+42+52=50

=242597-388972

=242597-16

=2425-155297=87397

=9

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About this question

This is a previous-year question from JEE Main 2017, 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.