Consider a workstation with $11$ machines $($in parallel$)$ each requiring one hour of process

time per job with scv of c$2$e

$=5.$ Each machine costs $$10$; $000.$ Orders for jobs arrive

at a rate of $10$ per hour with scv of $1$ and must be lled. Management has specied a

maximum allowable average response time $($i$.$e$.,$ time a job spends at the station$)$ of $2$

hours. Currently it is just over $3$ hours $($check it$).$

Analyze the following options for reducing average response time.

a$)$ Perform more preventive maintenance so that mr and mf are reduced, but mr$=$mf

remains the same. This costs $$8$; $000$ and does not improve the average process

time but does reduce the scv of processing time c$2$e

to one.

b$)$ Add another machine to the workstation at a cost of $$10$; $000.$ The new machine

is identical to existing machines, so te $=1$ and c$2$e

$=5.$

c$)$ Modify the existing machines to make them faster without changing the scv$,$ at

a cost of $$8$; $500.$ The modied machines would have te $=0$:$96$ and c$2$e

$=5.$