If the mean and the variance of $6,4, a, 8, b, 12,10, 13$ are $9$ and $9.25$ respectively, then $a+b+a b$ is equal to :

  • [JEE MAIN 2025]
  • A
    $105$
  • B
    $103$
  • C
    $100$
  • D
    $106$

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  • [JEE MAIN 2024]

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  • [JEE MAIN 2023]

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