JEE Main 2020MathematicsStatisticsHardNumerical

JEE Main 2020 — Statistics Question with Solution

JEE Main 2020 (06 Sep Shift 2)

Question

Consider the data on x taking the values 0, 2, 4, 8, ....., 2n with frequencies C0n, C1n, C2n,...., Cnn respectively. If the mean of this data is 7282n, then n is equal to ....... .

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Show full solutionCorrect answer: 6
Correct answer
6

Step-by-step explanation

xi (observation) 0 2 22................ 2n
fi (frequency) C0n C1n C2n............. Cnn

x¯=ΣfixiΣfi

0×C0n+2×C1n+22×C2n.....2n×CnnC0n+C1n+C2n.....+Cnn=3n-12n=7282n

⇒  3n=36

⇒ n=6

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About this question

This is a previous-year question from JEE Main 2020, 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.