OPM 3000 EXAM 2 PRE QUIZZES QUESTIONS AND
ANSWERS
Which of the following statements about queues is FALSE when demand exceeds supply? - CORRECT
ANSWER✅✅The queue grows as long as the supply rate exceeds capacity.
________ and ________ are ways to reduce a queue by adjusting DEMAND. - CORRECT
ANSWER✅✅Peak-load pricing, off-peak discount
Which of the following is a way to reduce a queue by adjusting CAPACITY? - CORRECT
ANSWER✅✅Minimize the amount of work that needs to be done during peak time (pre-processing
strategy).
What is the key assumption for the single-server queue model? - CORRECT ANSWER✅✅The average
interarrival time is greater than the average process time.
p<a
Which of the following statements is FALSE regarding the waiting time in a single-server queue model?
- When capacity decreases, the average waiting time increases.
- When the processing time decreases, the average waiting time decreases.
- When variability in the arrival or service process increases, the average waiting time increases.
- When utilization increases, the average waiting time decreases. - CORRECT ANSWER✅✅When
utilization (ratio between flow rate and process capacity; U = flow rate/capacity) increases, the average
waiting time decreases.
The drivers of waiting time in a single-server queue system include all of the following EXCEPT ______.
utilization, capacity, variability, learning - CORRECT ANSWER✅✅learning
,When a process has economies of scale in the operations of a system with queues, it means a
_________ queue system can be more _________. - CORRECT ANSWER✅✅bigger, efficient
An indicator of inefficiency in a separate queue system is ______. - CORRECT ANSWER✅✅having idle
servers and waiting customers at the same time
A pooled queue system increases the _________ of the __________ process. - CORRECT
ANSWER✅✅flexibility, supply
Which of the following statements is TRUE about economies of scale in queuing systems? - CORRECT
ANSWER✅✅A large system is more efficient than a small system.
A summer camp that offers one-week programs faces the challenges of long queues as parents try to
check in their children each Saturday morning. If they were to add more staff to assist with the check-in
process, then which of the following will occur?
1) The average time parents wait decreases.
2) The maximum time the parents wait decreases.
3) The average number of parents waiting to check in their child decreases. - CORRECT ANSWER✅✅all
three options
Queuing system A has a utilization of 80 percent, and queuing system B has a utilization of 90 percent.
Both have a single server. Say the utilization of both systems increases by 5 percent; that is, A increases
from 80 percent to 85 percent while B increases from 90 percent to 95 percent. Which system is likely to
experience the bigger change in the average time in queue? - CORRECT ANSWER✅✅System B
system A; utilization = 80% -> 85%
system B; utilization = 90% -> 95%
Time in queue increases at a faster rate as the utilization increases.
, The following four graphs (Figure 16.15 A, B, C, and D) display the number of customers in a queuing
system (y-axis) over a long period of time (x-axis). Which of the following is most likely a stable system? -
CORRECT ANSWER✅✅The one that's most linear is the stable queue system
Which of the following best reflects pooling capacity to reduce restroom queue lengths? - CORRECT
ANSWER✅✅Convert the separate men's and women's rooms into a single unisex restroom (that both
men and women can use).
YourNurse (YN) Inc. uses certified nurses to answer medical queries from customers over the phone.
When patients call into YN, they are first asked to provide their zip code, which then allows YN to route
their call to the call center nearest to the patient (it operates 10 across the country). Which single
suggestion in the following list (and explanation) is most likely to reduce the average time callers wait
before speaking with a nurse? - CORRECT ANSWER✅✅Instead of using callers' zip codes, route calls to
the call center with the fewest callers to help prevent situations in which there are idle nurses at the
same time that there are callers on hold.
Which of the following is NOT a useful technique to reduce the average waiting time during a peak
demand period in which the demand rate exceeds capacity?
- A city charges cars an extra fee for entering the downtown area during rush hour.
- A restaurant cuts ingredients in the morning ahead of the lunch rush.
- A package delivery company hires independent contractors to assist in the deliveries during the holiday
season.
- TSA decreases the coefficient of variation of passenger screening times at the airport.
- A cruise line requests passengers to select what items they will select from a menu four hours before
dinner is served on the ship. - CORRECT ANSWER✅✅TSA decreases the coefficient of variation of
passenger screening times at the airport.
With an unstable queue (demand exceeds capacity), reducing variability is not effective for reducing the
average queue length.
Suppose processing times and the coefficients of variation of interarrival times and processing times are
held constant. If utilization is increased from 80 percent to 90 percent, which of the following systems
experiences the largest increase in the average waiting time in queue? - CORRECT ANSWER✅✅A queue
with 1 server. (the lesser amount of servers, the higher impact) Queues with more servers experience
ANSWERS
Which of the following statements about queues is FALSE when demand exceeds supply? - CORRECT
ANSWER✅✅The queue grows as long as the supply rate exceeds capacity.
________ and ________ are ways to reduce a queue by adjusting DEMAND. - CORRECT
ANSWER✅✅Peak-load pricing, off-peak discount
Which of the following is a way to reduce a queue by adjusting CAPACITY? - CORRECT
ANSWER✅✅Minimize the amount of work that needs to be done during peak time (pre-processing
strategy).
What is the key assumption for the single-server queue model? - CORRECT ANSWER✅✅The average
interarrival time is greater than the average process time.
p<a
Which of the following statements is FALSE regarding the waiting time in a single-server queue model?
- When capacity decreases, the average waiting time increases.
- When the processing time decreases, the average waiting time decreases.
- When variability in the arrival or service process increases, the average waiting time increases.
- When utilization increases, the average waiting time decreases. - CORRECT ANSWER✅✅When
utilization (ratio between flow rate and process capacity; U = flow rate/capacity) increases, the average
waiting time decreases.
The drivers of waiting time in a single-server queue system include all of the following EXCEPT ______.
utilization, capacity, variability, learning - CORRECT ANSWER✅✅learning
,When a process has economies of scale in the operations of a system with queues, it means a
_________ queue system can be more _________. - CORRECT ANSWER✅✅bigger, efficient
An indicator of inefficiency in a separate queue system is ______. - CORRECT ANSWER✅✅having idle
servers and waiting customers at the same time
A pooled queue system increases the _________ of the __________ process. - CORRECT
ANSWER✅✅flexibility, supply
Which of the following statements is TRUE about economies of scale in queuing systems? - CORRECT
ANSWER✅✅A large system is more efficient than a small system.
A summer camp that offers one-week programs faces the challenges of long queues as parents try to
check in their children each Saturday morning. If they were to add more staff to assist with the check-in
process, then which of the following will occur?
1) The average time parents wait decreases.
2) The maximum time the parents wait decreases.
3) The average number of parents waiting to check in their child decreases. - CORRECT ANSWER✅✅all
three options
Queuing system A has a utilization of 80 percent, and queuing system B has a utilization of 90 percent.
Both have a single server. Say the utilization of both systems increases by 5 percent; that is, A increases
from 80 percent to 85 percent while B increases from 90 percent to 95 percent. Which system is likely to
experience the bigger change in the average time in queue? - CORRECT ANSWER✅✅System B
system A; utilization = 80% -> 85%
system B; utilization = 90% -> 95%
Time in queue increases at a faster rate as the utilization increases.
, The following four graphs (Figure 16.15 A, B, C, and D) display the number of customers in a queuing
system (y-axis) over a long period of time (x-axis). Which of the following is most likely a stable system? -
CORRECT ANSWER✅✅The one that's most linear is the stable queue system
Which of the following best reflects pooling capacity to reduce restroom queue lengths? - CORRECT
ANSWER✅✅Convert the separate men's and women's rooms into a single unisex restroom (that both
men and women can use).
YourNurse (YN) Inc. uses certified nurses to answer medical queries from customers over the phone.
When patients call into YN, they are first asked to provide their zip code, which then allows YN to route
their call to the call center nearest to the patient (it operates 10 across the country). Which single
suggestion in the following list (and explanation) is most likely to reduce the average time callers wait
before speaking with a nurse? - CORRECT ANSWER✅✅Instead of using callers' zip codes, route calls to
the call center with the fewest callers to help prevent situations in which there are idle nurses at the
same time that there are callers on hold.
Which of the following is NOT a useful technique to reduce the average waiting time during a peak
demand period in which the demand rate exceeds capacity?
- A city charges cars an extra fee for entering the downtown area during rush hour.
- A restaurant cuts ingredients in the morning ahead of the lunch rush.
- A package delivery company hires independent contractors to assist in the deliveries during the holiday
season.
- TSA decreases the coefficient of variation of passenger screening times at the airport.
- A cruise line requests passengers to select what items they will select from a menu four hours before
dinner is served on the ship. - CORRECT ANSWER✅✅TSA decreases the coefficient of variation of
passenger screening times at the airport.
With an unstable queue (demand exceeds capacity), reducing variability is not effective for reducing the
average queue length.
Suppose processing times and the coefficients of variation of interarrival times and processing times are
held constant. If utilization is increased from 80 percent to 90 percent, which of the following systems
experiences the largest increase in the average waiting time in queue? - CORRECT ANSWER✅✅A queue
with 1 server. (the lesser amount of servers, the higher impact) Queues with more servers experience
