Answer:
[tex]\mathbf{\mu_S = 12 }[/tex]; [tex]\text{Elroy can expect to roller skate and weight train, on average, 12 }[/tex][tex]\text{hours in a typical week.}[/tex]
Step-by-step explanation:
Given that:
The mean [tex]\mu_X = 5[/tex]
The mean [tex]\mu_Y = 7[/tex]
Where;
[tex]S= X+ Y[/tex]
[tex]\mu_S = \mu _X + \mu_Y \\ \\ \mu_S = 5+7 \\ \\ \mu_S = 12[/tex]
Thus;
[tex]\mathbf{\mu_S = 12 }[/tex];[tex]\text{ Elroy can expect to roller skate and weight train, on average, 12 }[/tex][tex]\text{hours in a typical week.}[/tex]