Your two ways are not different: they give the same result. You can use algebra to check that $$ \frac{x_1+\dotsm+x_n+\bar{x}}{n+1}=\bar{x} $$ where $\bar{x} = \frac{x_1+\dotsm+x_n}{n}$ is the mean.
kjetil b halvorsen ♦
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