The mean and variance of $20$ observations are found to be $10$ and $4,$ respectively. On rechecking, it was found that an observation $9$ was incorrect and the correct observation was $11$. Then the correct variance is

  • [JEE MAIN 2020]
  • A

    $3.99$

  • B

    $3.98$

  • C

    $4.02$

  • D

    $4.01$

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