University is considering offering its students the opportunity to get a flu vaccine ('flu shot'). The school is considering setting up the operation for just one day during the lunch hour. For a preliminary analysis, consider the following simplified description of the proposed operation: a total of 600 students will arrive at the cafeteria during the 12:00 Noon to 1:00 PM lunch hour. The students will arrive uniformly over time with no variability. No students will show up either before or after the lunch hour. Since 20% of the students have never had a flu shot, they first must go to a nurse practitioner for a quick review of their medical history. After this review, they then join a line waiting for vaccination by a doctor. The remaining 80% go straight to the line waiting for vaccination. (It is assumed that all the students will receive the vaccine.) There are 3 nurse practitioners available to review medical histories. Each nurse practitioner can review a student's medical history in 2 minutes. There are 4 doctors giving the vaccinations. It takes only 30 seconds for a doctor to vaccinate a student. Questions: What is the maximum build-up of students at the nurse-practitioner review? What is the maximum wait at the nurse-practitioner review? At what time will the line at the review be empty? At what time will the vaccination line be empty? (Note that it might be possible for the vaccination line to be empty even though the review line is not empty.)
Added by Rachel C.
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Count the number of students in the cafeteria. 600. Show more…
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