A simple random sample of 100 high school upperclassmen was selected from a large school district. The grade level of each student was recorded, and each student was asked the following questions:
A. Have you ever had a part-time job?
B. If you answered yes to the previous question, was your part-time job in the summer only?
| Uperclasssmen Job Data | ||||
|---|---|---|---|---|
| Grade | Job Experience | Total | ||
| Never Had Job | Summer Only | Year Round | ||
| 11th | 21 | 15 | 12 | 48 |
| 12th | 31 | 13 | 8 | 52 |
| Total | 52 | 28 | 20 | 100 |
Because this was a sample of about 50 students per grade from what is
described as a large school district we cannot draw definitive
parameters from this data, it would be helpful if more students could be
surveyed. The display in part (a) reveals that for our random sample a
larger percentage of Juniors have had a job than Seniors both year round
and only in the summer. We also see that the upperclassmen are almost
evenly split between never having a job and having a part time job.