The mean and $S.D.$ of the marks of $200$ candidates were found to be $40$ and $15$ respectively. Later, it was discovered that a score of $40$ was wrongly read as $50$. The correct mean and $S.D.$ respectively are...

  • A

    $14.98, 39.95$

  • B

    $39.95, 14.98$

  • C

    $39.95, 224.5$

  • D

    None of these

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