The mean of $n$ observations $x_{1}, x_{2}, \ldots, x_{n}$ is $\bar{x}$. If an observation $x_{q}$ is replaced by $x_{q}^{\prime}$, then the new mean is:

  • A
    $\bar{x} - x_{q} + x_{q}^{\prime}$
  • B
    $\frac{(n-1) \bar{x} + x_{q}^{\prime}}{n}$
  • C
    $\frac{(n-1) \bar{x} - x_{q}^{\prime}}{n}$
  • D
    $\frac{n \bar{x} - x_{q} + x_{q}^{\prime}}{n}$

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