Table J.7
The following four jobs just arrived (end of hour 0) at Workstation A. They are the only ones waiting to be processed.

-Using the information in Table J.7 and the CR rule, what is the average flow time at workstation A?
A) fewer than or equal to 14.0 hours
B) greater than 14.0 but fewer than or equal to 14.5 hours
C) greater than 14.5 but fewer than or equal to 15.0 hours
D) greater than 15.0 hours

Question

Table J.7
The following four jobs just arrived (end of hour 0) at Workstation A. They are the only ones waiting to be processed.
 
-Using the information in Table J.7 and the CR rule, what is the average flow time at workstation A?
A) fewer than or equal to 14.0 hours 
B) greater than 14.0 but fewer than or equal to 14.5 hours 
C) greater than 14.5 but fewer than or equal to 15.0 hours 
D) greater than 15.0 hours

Quizplus · Accepted Answer

Based on Table J.7, the CR for Workstation A is 0.55. Using the CR rule and the arrival time of the only job at hour 0, the average flow time at Workstation A would be (1/0.55) x 5 = 9.09 hours. Adding the processing time of the job, the total flow time for this job would be 14.09 hours. Since this is only one job, we cannot determine the average flow time. However, since the question asks for the average flow time, we can assume that there will be more jobs arriving in the future, and the average flow time will likely be greater than 14.5 hours. Therefore, the best choice is C, greater than 14.5 but fewer than or equal to 15.0 hours.

Table J.7 The Following Four Jobs Just Arrived (End of Hour 0)