Answer
All the ages are betweem the lower and upper fence. So, there are no outliers. And, if there are no outliers in the explanatory variables, there are no influential observations.
Work Step by Step
In MINITAB, enter the Age values in C1
Select Stats -> Basic Stas -> Display Descriptive Statistics
In Variables enter C1 and click in Statistics.
Select "First quartle", "Third quartile" and "Interquartile range". Click OK.
Click Ok.
$Q_1=35$, $Q_3=53.5$ and $IQR=18.5$
$Lower~Fence=Q_1-1.5(IQR)=35-1.5\times18.5=7.25$
$Upper~Fence=Q_3+1.5(IQR)=53.5+1.5\times18.5=81.25$
