Answer
$s=58~min$
$IQR=56.5~min$
Work Step by Step
In MINITAB, insert all the values of the table in the column C1.
Select Calc -> Column Statistics
In "Statistic" select "Standard deviation".
In "Input variable" enter C1.
Click OK.
The result for the standard deviation will be given.
$s=58$
$IQR=56.5$ (see problem 25)
