Question

A set of jobs A, B, C, D, E, F, G, H arrive at time t = 0 for processing on turning and grinding machines. Each jobs needs to be processed in sequence-first on the turning machine and second on the grinding machine, and the grinding must occur immediately after turning. The processing times of the jobs are given by

Job	A	B	C	D	E	F	G	H
Turning (minutes)	2	4	8	9	7	6	5	10
Grinding (minutes)	6	1	3	7	9	5	2	4

If the makespan is to be minimized, then the optimal sequence in which these jobs must be processed on the turning and grinding machines is

• A. B-G-C-H-F-D-E-A
• B. A-D-E-F-H-C-G-B
• C. G-E-D-F-H-C-A-B
• D. A-E-D-F-H-C-G-B

Answer 1

The correct option is D A-E-D-F-H-C-G-B

Sequencing,

A E D F H C G B