Let the mean and variance of four numbers $3,7, x$ and $y(x>y)$ be $5$ and $10$ respectively. Then the mean of four numbers $3+2 \mathrm{x}, 7+2 \mathrm{y}, \mathrm{x}+\mathrm{y}$ and $x-y$ is ..... .

  • [JEE MAIN 2021]
  • A

    $10$

  • B

    $11$

  • C

    $12$

  • D

    $48$

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