The administration of Kaplan college has generally assumed that the average
age of a student is no more than 20 years. However, lately the students have
appeared to be older than before, and some administrators say that the
average age could be higher than 20 years. You collected a random sample
of 40 students’ ages and discovered it had a mean of 20.76 and standard
deviation of 3.6. At the 0.10 level of significance, can you conclude that the
average age of students has indeed increased?