The production manager must determine the processing sequence for seven jobs through the grinding and then deburring departments. The same sequence will be followed in both departments. The manager$$s goal is to move the jobs through the two departments as quickly as possible. The foreman of the deburring department wants the SPT rule to be used to minimize the work$-$in$-$process inventory in his department.

PROCESSING TIME

$($hours$)$

Job Grinding Deburring

A $36$

B $24$

C $15$

D $43$

E $94$

F $87$

G $62$

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a$.$ Prepare a schedule using SPT for the grinding department.

b$-1.$ What is the total flow time in the grinding department for the SPT sequence?

b$-2.$ What is the makespan to process the seven jobs in both the grinding and deburring departments?

c$-1.$ Determine a sequence that will minimize the total time needed to process the jobs in both departments.