A college administrator wants to study the average age of students who drop out of college after attending only one semester. He randomly selects 25 students who are in this group. Their ages are listed below:
35.6 20.1 18.1 21.3 20.1 19.2 18.5 18.9 18.6 18.4 19.2
18.8 17.7 21.0 19.3 24.2 19.0 19.6 18.6 19.4 20.3 20.4
19.6 19.9 19.2
Because the administrator has been doing these studies in the past, he knows that age is normally distributed with a standard deviation of 0.8 years.
a. Find a 95% confidence interval for the mean age of all first semester college dropouts.
b. Interpret your results in part (a) in words.