Answer
$Lower~fence=30.625~miles~per~gallon$
$Upper~fence=47.225~miles~per~gallon$
$47.5~miles~per~gallon$ is an outlier.
Work Step by Step
$Lower~fence=Q_1-1.5\times IQR=36.85-1.5\times4.15=30.625$
$Upper~fence=Q_3+1.5\times IQR=41.0+1.5\times4.15=47.225$
There is no data value less than 30.625. But, $47.5\gt47.225$
