If the following jobs are sequenced according to the SPT rule then the maximum job tardiness (in days)is (assume zero for today's date)
A)26 days
B)16 days
C)10 days
D)5.2 days

Question

If the following jobs are sequenced according to the SPT rule then the maximum job tardiness (in days)is (assume zero for today's date) 
A)26 days 
B)16 days 
C)10 days 
D)5.2 days

Quizplus · Accepted Answer

Using the SPT rule, we sequence the jobs as follows:
1. Job E (processing time = 3, due date = 15)
2. Job A (processing time = 2, due date = 10)
3. Job B (processing time = 4, due date = 16)
4. Job C (processing time = 5, due date = 18)
5. Job D (processing time = 2, due date = 6)

Job tardiness is calculated as the difference between the completion date and the due date. Using the SPT rule, the completion times for each job are:
- Job E: day 3
- Job A: day 5
- Job B: day 9
- Job C: day 14
- Job D: day 16

Therefore, the job tardiness for each job is:
- Job E: 0
- Job A: 0
- Job B: 0
- Job C: 4
- Job D: 10

The maximum job tardiness is 10 days (for job D), which corresponds to choice (B). Therefore, the best choice is B.

If the Following Jobs Are Sequenced According to the SPT