Answer
The populations do not have the same variance.
Work Step by Step
In MINITAB, enter the Mixture 67-0-301 values in C1, the Mixture 67-0-400 values in C2 and in C3 enter the Mixture 67-0-353 values.
Select Stat -> Basic Statistics -> Display Descriptive Statistics
In Variables enter C1 C2 C3
Click in Statistics. Select standard deviation. Click OK.
Click Ok.
$385\gt2\times107.8$
