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

    $2$

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