Let mathrm{n} be an odd natural number such that variance of 1,2,3,4, ldots, mathrm{n} is 14 . Then

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Let $\mathrm{n}$ be an odd natural number such that the variance of $1,2,3,4, \ldots, \mathrm{n}$ is $14 .$ Then $\mathrm{n}$ is equal to ..... .

A

$12$

B

$13$

C

$23$

D

$26$

(JEE MAIN-2021)

Solution

$\frac{\mathrm{n}^{2}-1}{12}=14 \Rightarrow \mathrm{n}=13$

Standard 11

Mathematics

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