The purpose of a study by Moneim et al. (A-26) was to examine thumb amputations from team roping at rodeos. The researchers reviewed 16 cases of thumb amputations. Of these, 11 were complete amputations while five were incomplete. The ischemia time is the length of time that insufficient oxygen is supplied to the amputated thumb. The ischemia times (hours) for 11 subjects experiencing complete amputations were 4:67; 10:5; 2:0; 3:18; 4:00; 3:5; 3:33; 5:32; 2:0; 4:25; 6:0 For five victims of incomplete thumb amputation, the ischemia times were 3:0; 10:25; 1:5; 5:22; 5:0 Treat the two reported sets of data as sample data from the two populations as described.

Construct a 95 percent confidence interval for the ratio of the two unknown population variances.