Salut!
[tex]M_p=\frac{p_{1}*a_{1}+p_{2}*a_{2}+...+p_{n}*a_{n}}{p_{1}+p_{2}+...+p_{n}}\\
[/tex]
[tex]a_{1}=2\sqrt{6},~~p_{1}=4\\
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a_{2}=7\sqrt{6},~~p_{2}=6[/tex]
[tex]M_{p}=\frac{2\sqrt{6}*4+7\sqrt{6}*6}{4+6}\\
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M_{p}=\frac{8\sqrt{6}+42\sqrt{6}}{10}\\[/tex]
[tex]M_{p}=\frac{50\sqrt{6} }{10}\\\\
M_{p}=5\sqrt{6}
[/tex]
