Doing Time. The Federal Bureau of Prisons publishes data in Prison Statistics on the times served by prisoners released from federal institutions for the first time. Independent random samples of released prisoners in the fraud and firearms offense categories yielded the following information on time served, in months.

Fraud Firearms 3.6 17.9 25.5 23.8 5.3 5.9 10.4 17.9 10.7 7.0 18.4 21.9 8.5 13.9 19.6 13.3 11.8 16.6 20.9 16.1 At the 5% significance level, do the data provide sufficient evidence to conclude that the mean time served for fraud is less than that for firearms offenses? (Note: x¯1 = 10.12, s1 = 4.90, x¯2 = 18.78, and s2 = 4.64.)