Crawford Industries Purchases Step-Down Electrical Converters from Two Suppliers

Multiple Choice

Crawford Industries purchases step-down electrical converters from two suppliers.The converters from the two suppliers appear to have the same average life (measured in hours) but the variability in useful life appears be different for the two suppliers.In random samples of 8 converters from supplier A and 8 converters from supplier B, the variance in sample A was 1600; the variance in sample B was 3800.Assume that the life of the converters is normally distributed in each population.Test the null hypothesis that the variance of population B is no greater than the variance of population A, against the alternative hypothesis that the variance of population B is greater than the variance of population A..Use a significance level of 5% and report the F statistic (F_stat) for this one-tailed test.

A) 3.160
B) 6.013
C) 2.375
D) 2.965