Calculating the f-stat to determine the difference between preservatives

The use of preservatives by food processors has become a controversial issue. Suppose two preservatives are extensively tested and determined safe for use in meats. A processor wants to compare the preservatives for their effects on retarding spoilage. Suppose 15 cuts of fresh meat are treated with preservative A and 15 are treated with preservative B, and the number of hours until spoilage begins is recorded for each of the 30 cuts of meat. The results are summarized in the table below.

Preservative A Preservative B
A = 106.4 hours B = 96.54 hours
SA = 10.3 hours SB = 13.4 hours

Referring to the table, which of the following is the correct test statistic for determining if the population variancediffer for preservatives A and B ?

A. F = -3.10
B. F = 0.5908
C. F = 0.7687
D. F = 0.8250

The solution calculates an f-stat to determine the difference in the variance of two useful preservatives.