Question $5$

Purple Rose is an ATV rental shop located near a resort, which rents out ATVs to guests stay in the resort. When a customer requests to rent an ATV and no ATVs are available $($they are either with another customers or being cleaned for rental$),$ customer waits until an ATV is available. Once an ATV is rented out to a customer, the customer keeps it for an average of $1$ hour $($i$.$e$.,60$ minutes$).$ Upon return, the ATV is cleaned and tuned$-$up$,$ which takes about $15$ minutes.

Suppose Purple Rose has $7$ ATVs, and demand for ATV rental is $3\mathrm{.}36$ per hour. What is the average amount of time a customer waits to receive an ATV?

$($Hint: From the perspective of customer waiting time, $15$ minutes of cleaning time would be part of "processing time". Assume CVa$=CVp=1$ in your calculations$).$

$27$ minutes

$1$ minute

$3$ minutes

$6$ minutes