Four trucks, 1, 2, 3, and 4, are waiting on a loading dock at XYZ Company that hasonly a single service bay. The trucks are labeled in the order that they arrived at thedock. Assume the current time is 1:00 P.M. The times required to unload each truck and the times that the goods they contain are due in the plant are given in thefollowing table.Truck Unloading Time (minutes) Time Material Is Due1 20 1:25 P.M.2 14 1:45 P.M.3 35 1:50 P.M.4 10 1:30 P.M.Determine the schedules that result for each of the rules FCFS, SPT, EDD, andCR. In each case compute the mean flow time, average tardiness, and number oftardy jobs.

Four trucks, 1, 2, 3, and 4, are waiting on a loading dock at XYZ Company that hasonly a single service bay. The trucks are labeled in the order that they arrived at thedock. Assume the current time is 1:00 P.M. The times required to unload each truck and the times that the goods they contain are due in the plant are given in thefollowing table.Truck Unloading Time (minutes) Time Material Is Due1 20 1:25 P.M.2 14 1:45 P.M.3 35 1:50 P.M.4 10 1:30 P.M.Determine the schedules that result for each of the rules FCFS, SPT, EDD, andCR. In each case compute the mean flow time, average tardiness, and number oftardy jobs.

Practical Management Science

6th Edition

ISBN:9781337406659

Author:WINSTON, Wayne L.

Publisher:WINSTON, Wayne L.

Chapter12: Queueing Models

Section: Chapter Questions

Problem 59P

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Five jobs are waiting for processing through two work centers. Their processing time (in minutes) at each work center is contained in the table below. Each job requires work center Alpha before work center Beta. According to Johnson's rule, which job should be scheduled first in the sequence? O A. V OB. U O C. R OD. S O E. T Job R S T Alpha 20 23 50 26 55 Beta 34 35 20 26 75
(10 Points) Eat well is a small drive through fast food restaurant, staffed by anefficient employee John, is located in a super mall area. Customers arrive at thecounter at an average of one every 15 minutes, and the customer arrival followsa Poisson distribution. John takes at most 10 minutes to process each foodorder.a) What is average number of customer being served at any time?b) The expected number of customers waiting to be served.c) Compute the average time customer wait in the system.d) Compute the average time customer wait in the line.e) What percentage of time is John Idle?
In question 4, why did we consider the needed waiting for trucks from 6pm to 8am?
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