A study of the operation of a parking garage showed that, in the past, the average parking time was 220 minutes. Recently, the garage was remodeled and charges increased. The management wants to know...

A study of the operation of a parking garage showed that, in the past, the average parking time was 220 minutes. Recently, the garage was remodeled and charges increased. The management wants to know if the changes have had any effect on mean parking time. A random sample of 25 cars had an average parking time of 208 minutes and a standard deviation of 40 minutes. Use alpha = 0.05 and assume parking times are normally distributed.