You$$ve been hired as a consultant for a local electronics repair shop called $$TechFix$.$ They

specialize in repairing smartphones and laptops. TechFix has a $2$ step process. When a repair

arrives, they first go through a diagnostic process where a diagnostic technician evaluates the

needed repairs and estimates the cost of the repairs. The second step is to go to the

appropriate repair station. They have a repair station for Smartphones that is staffed by a

Smartphone Repair Technician and they have a repair station for Laptops that is staffed by a

Laptop Repair Technician.

The shop is open $7$ days a week from $9$:$00$ AM $7$:$00$ PM$.$ On average $1$ repair order arrives per

hour during this time. During this $10$ hour period, the shop is staffed by $1$ Diagnostic Technician,

$1$ Laptop Repair Technician, and $1$ Smartphone Repair Technician. At the end of the day, if a

technician is working on a repair, the work will be preempted and started again the next day.

$($Hint: use the preempt Schedule Rule in your model.$)$

Of the repairs that come in$,$ roughly half of them are for Smartphones and the other half are for

Laptops. Of the smartphone repairs, $60\%$ are minor and $40\%$ are major repairs. Of the laptop

repairs, $30\%$ are minor and $70\%$ are major repairs. The service times are at each step in the

process are listed below.

Smartphone Laptop

Diagnosis Uniform $15$ to $30$ minutes Uniform $30$ to $45$ minutes

Minor Repair Normal with mean of $1$ hour

and standard deviation of $\mathrm{.}2$

hours

Normal with mean of $1\mathrm{.}5$

hours and standard deviation

of $\mathrm{.}2$ hours

Major Repair Normal with mean of $3$ hours

and standard deviation of $\mathrm{.}5$

hours

Normal with mean of $4$ hours

and standard deviation of $\mathrm{.}5$

hours

Run the model for $30$ days and $100$ replications. Use a base time unit of hours. Keep track of the

time that a smartphone and laptop are in the system $($including the overnight hours.$)$ For

example, if a smartphone comes in at $10$:$00$ AM on Monday and is finished at $11$:$00$ AM on

Tuesday, it would have been in the system for $25$ hours.

Round all answers to $2$ decimal places.

a$.$ Fill in the following table:

Measure Average

Smartphones Time in System

Laptops Time in System

Diagnostic Tech Scheduled

Utilization

Smartphone Repair Tech

Scheduled Utilization

Laptop Repair Tech Scheduled

Utilization

b$.$ If you could add $1$ more resource to the system, what resource would you add and why