Independent random samples of released prisoners in the fraud
and firearms offense categories yielded the given information on
time served, in months. At the 1% significance level, do the data
provide sufficient evidence to conclude that the mean time served
for fraud is less than that for firearms offenses? Assume that
populations standard deviations are same for both group. (i.e., we
assume σ1 = σ2 .) What is the parameter of interest? What is the
underlying distribution?
Fraud: 15.2, 11.2,...