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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