The half life period of a radioactive element $X$ is same as the mean life time of another radioactive element $Y$. Initially both of them have the same number of atoms. Then

  • [IIT 1999]
  • A

    $X$ and $Y$ have the same decay rate initially

  • B

    $X$ and $Y$ decay at the same rate always

  • C

    $Y$ will decay at a faster rate than $X$

  • D

    $X$ will decay at a faster rate than $Y$

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  • [AIIMS 2000]