The mean and standard deviation of $15$ observations are found to be $8$ and $3$ respectively. On rechecking it was found that, in the observations, $20$ was misread as $5$ . Then, the correct variance is equal to......

  • [JEE MAIN 2022]
  • A

    $7$

  • B

    $20$

  • C

    $19$

  • D

    $17$

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