The data set for 10 a.m. has 25 numbers and the number in the middle is 33, so this is the median age. Because the data set for 6 p.m. has 27 numbers and the number in the middle is 17, this is the median age. So it is more likely that younger, newer drivers will be at the library at 6 p.m., which makes it a better time for Kevin's presentation.