JEE Main 2023 — Statistics Question with Solution
From: JEE Main 2023 (Online) 6th April Morning Shift
Question
The mean and variance of a set of 15 numbers are 12 and 14 respectively. The mean and variance of another set of 15 numbers are 14 and respectively. If the variance of all the 30 numbers in the two sets is 13 , then is equal to :
Choose an option
Show full solutionCorrect option: C
Correct answer
C10
Step-by-step explanation
We know that if are the sizes, are the means and are the standard deviation of the series, then the combine variance of the series.
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This is a previous-year question from JEE Main 2023, 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.