If the variance of the frequency distribution is $3$ then $\alpha$ is ......

$X_i$ $2$ $3$ $4$ $5$ $6$ $7$ $8$
Frequency $f_i$ $3$ $6$ $16$ $\alpha$ $9$ $5$ $6$

 

  • [JEE MAIN 2023]
  • A

    $5$

  • B

    $4$

  • C

    $3$

  • D

    $2$

Similar Questions

If the variance of $10$ natural numbers $1,1,1, \ldots ., 1, k$ is less than $10 ,$ then the maximum possible value of $k$ is ...... .

  • [JEE MAIN 2021]

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The mean and the standard deviation $(s.d.)$  of five observations are $9$ and $0,$ respectively. If one of the observations is changed such that the mean of the new set of five observations becomes $10,$  then their $s.d.$  is?

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  • [AIEEE 2012]