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\begin{aligned}\mu_{\bar{X}} &=\Sigma \bar{x} P(\bar{x}) \\&=152\left(\frac{1}{16}\right)+154\left(\frac{2}{16}\right)+156\left(\frac{3}{16}\right)+158\left(\frac{4}{16}\right)+160\left(\frac{3}{16}\right)+162\left(\frac{2}{16}\right)+164\left(\frac{1}{16}\right) \\&=158\end{aligned}