Let the mean and the variance of 6 observation $a, b$, $68,44,48,60$ be $55$ and $194 $, respectively if $a>b$, then $a+3 b$ is

  • [JEE MAIN 2024]
  • A

    $200$

  • B

    $190$

  • C

    $180$

  • D

    $210$

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The number of values of $a \in N$ such that the variance of $3,7,12 a, 43-a$ is a natural number is  (Mean $=13$)

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