Answer
The requirement of equal population variances for each treatment is verified.
Work Step by Step
In MINITAB 18, enter the data according to the table below.
Select Stat -> Basic Statistics -> Display Descriptive Statistics
In Variables enter Time (C3). In By variables enter Gender Age (C1 C2).
Click in Statistics. Select Standard deviation. Click Ok.
Click Ok.
Lowest standard deviation: 0.275
Highest standard deviation: 0.532
But, $0.532\lt2\times0.275$
