Please do NOT use excel to solve lease do NOT use excel to solve Question 25 pts
ID: 3366896 • Letter: P
Question
Please do NOT use excel to solve
lease do NOT use excel to solve
Question 25 pts
When the earliest due date (EDD) rule is applied to the sample of jobs, the resulting sequence is:
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Question 35 pts
Average flow time for the sample of jobs when sequenced by the first come, first served (FCFS) rule is approximately:
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Question 45 pts
Average lateness for the sample of jobs when sequenced by the shortest processing time (SPT) rule is approximately:
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Question 55 pts
Average flow time for the sample of jobs when sequenced by the earliest due date (EDD) rule is approximately:
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Question 65 pts
Based on average flow time and average lateness results, the scheduling rule that appears most attractive given this sample of jobs is:
EFF, SDS, XC, RBP, ABC You are working as a summer intern at a small Cincinnati company that manufactures machine parts. The director of operations has asked you to review the company's practices for scheduling customer orders. Currently, the company schedules work on a first come, first served (FCFS) basis The director of operations is wondering whether a shortest processing time (SPT) or earliest due date (EDD) sequencing rule might work better. Using the data table in Table 1, compare the effectiveness of the current and two alternative sequencing rules. Table 1: Job Scheduling Data Job XC EFF ABC RBP SDS Date Order Received Mar 3 Mar 20 Feb 2 Febl1 Mar 8 Operating Time 3.2 4.5 6.0 2.9 Due Date 12 20 10 16 18Explanation / Answer
1)
The sequence for EDD is arrange according to due date smallest to largest
The sequence is ABC-XC-RBP-SDS-EFF
2)
Average flow time for the sample of jobs when sequenced by the first come, first served (FCFS) rule
The sequence for FCFS is arranged according to latest date order received
The sequence for FCFS is ABC-RBP-XC-SDC-EFF
The flow rate is obtained by adding the oprating time of previous and current job
Flow Time
4.5
4.5+6
=10.5
10.5+5.1
=15.6
15.6+2.9
=18.5
18.5+3.2
=21.7
3)
Average lateness for the sample of jobs when sequenced by the shortest processing time (SPT) rule is;
The sequence for SPT is arranged according to their oprerating time smallest to largest.
SPT sequence is SDS-EFF-ABC-XC-RBP
The lateness is calculated by subtracting due date by flow time
Flow Time
2.9
2.9+3.2
=6.1
6.1+4.5
=10.6
10.6+5.1
=15.7
15.7+6
=21.7
Lateness
2.9-18
=-15.1
6.1-20
=-13.9
10.6-10
=0.6
15.7-12
=3.7
21.7-16
=5.7
4)
Average flow time for the sample of jobs when sequenced by the earliest due date (EDD) rule is
The sequence is ABC-XC-RBP-SDS-EFF
5)
Based on average flow time and average lateness results, Shortest processing time (SPT) looks most attractive because it has lowest average flow time and has negative average lateness
Earliest Due Date Job ABC XC RBP SDS EFF Due Date 10 12 16 18 20