
Concept explainers
a)
To determine: Thesequence of jobs based on the decision rule, i.e, First Come First Served (FCFS).
Introduction: The First Come First Served is the
a)

Answer to Problem 15P
The sequence is A-B-C-D-E.
Explanation of Solution
Given information:
The following information has been given below:
Job | Due date | Duration (days) |
A | 313 | 8 |
B | 312 | 16 |
C | 325 | 40 |
D | 314 | 5 |
E | 314 | 3 |
All the jobs have arrived on day 275.
Determine the sequence of the job by using FCFS:
Job | Due date | Duration (days) | Flow time | Start | End | Lateness |
A | 313 | 8 | 8 | 275 | 282 | |
B | 312 | 16 | 24 | 283 | 298 | |
C | 325 | 40 | 64 | 299 | 338 | 13 |
D | 314 | 5 | 69 | 339 | 343 | 29 |
E | 314 | 3 | 72 | 344 | 346 | 32 |
Total | 72 | 237 | 74 |
Working note:
The duration and due date for the jobs has been given. The flow time is the cumulative value of the duration. The jobs arrival rate is given as 275.
End day of Job A:
The jobs arrival rate is given as 275. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job A is 282.
End day of Job B:
The start day of Job B is the next day of the end day of Job A. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job B is 298.
End day of Job C:
The start day of Job C is the next day of the end day of Job B. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job C is 338.
End day of Job D:
The start day of Job D is the next day of the end day of Job C. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job D is 343.
End day of Job E:
The start day of Job E is the next day of the end day of Job D. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job E is 346.
Lateness of Job A and Job B:
The end day of Job A and Job B is less than its respective due date. Hence, there is no lateness.
Lateness of Job C:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job C is 13.
Lateness of Job D:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job D is 29.
Lateness of Job E:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job E is 32.
b)
To determine: The sequence of jobs based on the decision rule, i.e, Earliest Due Date (EDD).
Introduction: The Earliest Due Date is the scheduling rule, which helps to arrange the sequence in the order. Here, the job with the earliest due date would be served first. Then, the process would be go on from the earliest due date to the latest due date.
b)

Answer to Problem 15P
The sequence is B-A-D-E-C.
Explanation of Solution
Given information:
The following information has been given below:
Job | Due date | Duration (days) |
A | 313 | 8 |
B | 312 | 16 |
C | 325 | 40 |
D | 314 | 5 |
E | 314 | 3 |
All the jobs have arrived on day 275.
Determine the sequence of the job by using EDD:
Job | Due date | Duration (days) | Flow time | Start | End | Lateness |
B | 312 | 16 | 16 | 275 | 290 | |
A | 313 | 8 | 24 | 291 | 298 | |
D | 314 | 5 | 29 | 299 | 303 | |
E | 314 | 3 | 32 | 304 | 306 | |
C | 325 | 40 | 72 | 307 | 346 | 21 |
Total | 72 | 173 | 21 |
Working note:
The duration and due date for the jobs have been given. The flow time is the cumulative value of the duration. The jobs arrival rate is given as 275. The job should be arranged based on the due date. The due date should be assembled in the ascending order.
End day of Job A:
The jobs arrival rate is given as 275. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job A is 290.
End day of Job B:
The start day of Job B is the next day of the end day of Job A. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job B is 298.
End day of Job C:
The start day of Job C is the next day of the end day of Job B. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job C is 303.
End day of Job D:
The start day of Job D is the next day of the end day of Job C. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job D is 306.
End day of Job E:
The start day of Job E is the next day of the end day of Job D. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job E is 346.
Lateness of Job A, Job B, Job C, and Job D is given below:
The end day of Job A, Job B, Job C, and Job dare less than its respective due date. Hence, there is no lateness.
Lateness of Job E:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job E is 21.
c)
To determine: The sequence of jobs based on the decision rule, i.e, Shortest Processing Time (SPT).
Introduction: The Shortest Processing Time is the scheduling rule, which helps to arrange the sequence in the order. Here, the job with the shortest duration is served first. Then, the process would be go on from the shortest to the largest duration.
c)

Answer to Problem 15P
The sequence is E-D-A-B-C.
Explanation of Solution
Given information:
The following information has been given below:
Job | Due date | Duration (days) |
A | 313 | 8 |
B | 312 | 16 |
C | 325 | 40 |
D | 314 | 5 |
E | 314 | 3 |
All the jobs are arrived on day 275.
Determine the sequence of the job by using SPT:
Job | Due date | Duration (days) | Flow time | Start | End | Lateness |
E | 314 | 3 | 3 | 275 | 277 | |
D | 314 | 5 | 8 | 278 | 282 | |
A | 313 | 8 | 16 | 283 | 290 | |
B | 312 | 16 | 32 | 291 | 306 | |
C | 325 | 40 | 72 | 307 | 346 | 21 |
Total | 72 | 131 | 21 |
Working note:
The duration and due date for the jobs have been given. The flow time is the cumulative value of the duration. The jobs arrival rate is given as 275. The job should be arranged based on the duration (processing time). The duration should be assembled in the ascending order.
End day of Job A:
The jobs arrival rate is given as 275. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job A is 277.
End day of Job B:
The start day of Job B is the next day of the end day of Job A. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job B is 282.
End day of Job C:
The start day of Job C is the next day of the end day of Job B. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job C is 290.
End day of Job D:
The start day of Job D is the next day of the end day of Job C. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job D is 306.
End day of Job E:
The start day of Job E is the next day of the end day of Job D. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job E is 346.
Lateness of Job A, Job B, Job C, and Job D is as follows:
The end day of Job A, Job B, Job C, and Job D are less than its respective due date. Hence, there is no lateness.
Lateness of Job E:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job E is 21.
d)
To determine: The sequence of jobs based on the decision rule, i.e, Longest Processing Time (LPT).
Introduction: The Largest Processing Tine is the scheduling rule, which helps to arrange the sequence in the order. Here, the job with the largest duration is served first. Then, the process would go on from the largest to the shortest duration.
d)

Answer to Problem 15P
The sequence is C-B-A-D-E.
Explanation of Solution
Given information:
The following information has been given below:
Job | Due date | Duration (days) |
A | 313 | 8 |
B | 312 | 16 |
C | 325 | 40 |
D | 314 | 5 |
E | 314 | 3 |
All the jobs have arrived on day 275.
Determine the sequence of the job by using LPT:
Job | Due date | Duration (days) | Flow time | Start | End | Lateness |
C | 325 | 40 | 40 | 275 | 314 | |
B | 312 | 16 | 56 | 315 | 330 | 18 |
A | 313 | 8 | 64 | 331 | 338 | 25 |
D | 314 | 5 | 69 | 339 | 343 | 29 |
E | 314 | 3 | 72 | 344 | 346 | 32 |
Total | 72 | 301 | 104 |
Working note:
The duration and due date for the jobs have been given. The flow time is the cumulative value of the duration. The jobs arrival rate is given as 275. The job is arranged based on the duration (processing time). The duration should be assembled in the descending order
End day of Job A:
The jobs arrival rate is given as 275. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job A is 314.
End day of Job B:
The start day of Job B is the next day of the end day of Job A. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job B is 330.
End day of Job C:
The start day of Job C is the next day of the end day of Job B. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job C is 338.
End day of Job D:
The start day of Job D is the next day of the end day of Job C. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job D is 343.
End day of Job E:
The start day of Job E is the next day of the end day of Job D. The end day is calculated by adding the start day with the value attained by subtracting 1 from the duration. Hence, the end day of Job E is 346.
Lateness of Job A:
The end day of Job A is less than its respective due date. Hence, there is no lateness.
Lateness of Job B:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job B is 18.
Lateness of Job C:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job C is 25.
Lateness of Job D:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job D is 29.
Lateness of Job E:
It is calculated by subtracting the end day of the job from the due date of the project. Hence, the lateness of Job E is 32.
Summary:
Decision rule | Average tardiness | Average flow time | Average number of jobs in system |
FCFS | 14.8 | 47.4 | 3.3 |
EDD | 4.2 | 34.6 | 2.4 |
SPT | 4.2 | 26.2 | 1.8 |
LPT | 20.8 | 60.2 | 4.2 |
First Come First Served (FCFS):
Average tardiness:
It is calculated by dividing the total lateness with the number of jobs. Hence, the average tardiness is 14.8.
Average flow time:
It is calculated by dividing the total flow time with the number of jobs. Hence, the average flow time is 47.4.
Average number of jobs in the system:
It is calculated by dividing the total flow time with the total duration of all the jobs. Hence, the average number of jobs in the system is 3.3.
Earliest Due Date (EDD):
Average tardiness:
It is calculated by dividing the total lateness with the number of jobs. Hence, the average tardiness is 4.2.
Average flow time:
It is calculated by dividing the total flow time with the number of jobs. Hence, the average flow time is 34.6.
Average number of jobs in the system:
It is calculated by dividing the total flow time with the total duration of all the jobs. Hence, the average number of jobs in the system is 2.4.
Shortest processing time (SPT):
Average tardiness:
It is calculated by dividing the total lateness with the number of jobs. Hence, the average tardiness is 4.2.
Average flow time:
It is calculated by dividing the total flow time with the number of jobs. Hence, the average flow time is 26.2.
Average number of jobs in the system:
It is calculated by dividing the total flow time with the total duration of all the jobs. Hence, the average number of jobs in the system is 1.8.
Largest processing time (LPT):
Average tardiness:
It is calculated by dividing the total lateness with the number of jobs. Hence, the average tardiness is 20.8.
Average flow time:
It is calculated by dividing the total flow time with the number of jobs. Hence, the average flow time is 60.2.
Average number of jobs in the system:
It is calculated by dividing the total flow time with the total duration of all the jobs. Hence, the average number of jobs in the system is 4.2.
Shortest processing time has the minimum average tardiness, average flow time, and the average number of jobs in systems. Hence, SPT is the best decision rule.
Want to see more full solutions like this?
Chapter 15 Solutions
Pearson eText Principles of Operations Management: Sustainability and Supply Chain Management -- Instant Access (Pearson+)
- Agan Interior Design provides home and office decorating assistance to its customers. In normal operation, an average of 2.6 customers arrive each hour. One design consultant is available to answer customer questions and make product recommendations. The consultant averages 10 minutes with each customer. (a) Compute the operating characteristics of the customer waiting line, assuming Poisson arrivals and exponential service times. (Round your answers to four decimal places. Report time in hours.) λ= μ = = L = Wa W = P. W h (b) Service goals dictate that an arriving customer should not wait for service more than an average of 5 minutes. Is this goal being met? (Round your answer to one decimal place.) W₁ (in minutes) = min, which is ---Select--- than the desired wait time, so the goal ---Select--- met. What action do you recommend? (Select all that apply.) Hire another consultant. Increase the hours of operation. Decrease the mean service rate. Increase the mean service rate. There is…arrow_forwardCommunication Tips (2015) Tactful bragging Respond to the question "So, what do you do?" Whether you are student or have a job/internship, how can you tactfully brag in your answer to this question? Use the three elements from the video (listed below) when crafting your brag statement: Focus on results vs title Process vs job description Loop back to listener Example of an instructor's brag statement: "I help hundreds of students each semester to connect with one another, develop communication skills and prepare for upcoming interviews. Through improv games we explore presence, flexibility, and storytelling. How have your networking experiences on campus been so far?"arrow_forwardAccounting problemarrow_forward
- Government's new plan to shift cargo from roads back to rail 26TH JANUARY 2024 Government is seeking to finalise a plan aimed at improving its rail network and move cargo away from a billion rand per day to its logistics crises, government has said an urgentturnaround is needed to improve its 31 000km locomotive network as more and more cargo moves from rail to trucks. The Department of Transport (DoT) hosted a discussion with industry stakeholders regarding the Freight Road to Rail Migration Plan on Thursday - the latest development in the wake of President Cyril Ramphosa forming the National Logistics Crisis Committee last year. Transnet, the South African National Roads Agency (Sanral) and private sector companies were all in attendance. The Freight Road to Rail Migration Plan is part of government's strategies to improve the country's ongoing logistics crises. In October last year, the government unveiled its Freight Logistics Roadmap to improve the ports and rail networks and…arrow_forwardAssess what led to such logistical inefficiencies / collapse of a previously world class freight networkarrow_forwardWhich of the following statements concerning the evaluation of training programs is true? Most companies thoroughly evaluate the return on investment of their training programs It is relatively easy to establish a control group and a treatment group for evaluation Results level of evaluation measures how well participants liked the program Behavior level criteria measure whether skills learned in training result in behavior changes back on the jobarrow_forward
- Eligibility testing is an disparate impact validation method none of the above a method to validate promotions and progressive discipline activity a test an employee administers to ensure that the potential employee is capable and qualified to perform the requirements of the positionarrow_forwardA no-strike pledge by a union in a collective bargaining agreement is given in return for management’s agreement to: a grievance procedure a union shop a wage increase a fringe benefit increase binding arbitration of grievancesarrow_forwardWhich is the major OD technique that is used for increasing the communication, cooperation, and cohesiveness of work units? Leadership analysis Developing objectives Groupthink Strategic Planning team Buildingarrow_forward
- An American multinational firm usually is less than fully successful in adapting itself to local practices in each country because: American managers are often ignorant of local conditions None of the above management direction may be centralized in the home office All of the above Foreign subsidiaries often have American managersarrow_forwardWhen salary increases are based on inputs, or performance, companies are following: agency theory equality theory equity theory compliance theory need theoryarrow_forwardThe most frequently used techniques for measuring job satisfaction involves Direct observation Questionnaires Interviews Psychological testsarrow_forward
- Practical Management ScienceOperations ManagementISBN:9781337406659Author:WINSTON, Wayne L.Publisher:Cengage,Foundations of Business (MindTap Course List)MarketingISBN:9781337386920Author:William M. Pride, Robert J. Hughes, Jack R. KapoorPublisher:Cengage LearningFoundations of Business - Standalone book (MindTa...MarketingISBN:9781285193946Author:William M. Pride, Robert J. Hughes, Jack R. KapoorPublisher:Cengage Learning


