Estimating total labor costs Dr. Barbara Benson is the head of the pathology laboratory at Barrington Medical Center in Mobile, Alabama. Dr. Benson estimates the amount of work for her laboratory staff by classifying the pathology tests into three categories: simple routine, simple non routine, and complex. She expects a simple routine test to require 4 hours of staff time. She estimates the demand for each type of test for June through August to be the following:



Laboratory staff salaries, including fringe benefits, average $3,600 per month. Each worker works 150 hours per month. If the hospital workload exceeds the available staff time, Dr. Benson has the tests performed at a neighboring private pathology laboratory that charges $80 for a simple routine test, $100 for a simple non-routine test, and $160 for a complex test. 
Dr. Benson is thinking of employing 20 to 27 workers. Because of the difficulty in hiring reliable workers, Barrington’s chief administrator has instructed her to employ laboratory staff for no shorter a period than one quarter. 
Required 
(a) Determine how many workers Dr. Benson should employ over the quarter to minimize the costs of performing the tests. What is the minimum cost? 
(b) Suppose the easy availability of experienced laboratory staff allows Barrington Medical Center to change staffing loads each month. Determine the number of workers Dr. Benson should hire each month in these circumstances to minimize the costs of performing tests. What is the minimum cost?