Quiz 4 Flashcards
It is generally true that, for a new product, revising the forecast after some actual sales will tend to:
None of the above.
Improve the accuracy of the forecast.
Reduce the accuracy of the forecast.
Have no effect on the accuracy of the forecast.
Improve the accuracy of the forecast.
Consider a machine that makes 6 parts in an hour and operates 2 hours per day. What is the machine utilization if the demand for the parts is 10 parts per hour and 6 machines are available to make the parts?
10%
28%
5%
13.9%
10/(6*6)
28%
Arrivals to a queue are random and service time variation is very high. Therefore a 15% capacity buffer is recommended. This means that:
The percentage of customers who wait will be 15%.
The arrival rate will be 15% lower than the service rate.
Servers will be busy serving customers 85% of the time
The planned server utilization will be 15%.
Servers will be busy serving customers 85% of the time
Consider a call center agent who spends about 10 minutes per customer and works for 8 hours per day. What is the agent utilization if on average 10 calls arrive per hour and three agents are available to answer the calls?
167%
4.4%
5%
56%
56%
When customers arrive independently of one another for a service, we can conclude that:
The service time is exponentially distributed
The queue size is limited
The time between arrivals will follow a normal distribution
The time between arrivals will follow an exponential distribution.
The time between arrivals will follow an exponential distribution.
Patients arrive to a clinic at the rate of 30 per hour. The clinic is open for 24 hours a day. The average service time for a patient is about 45 minutes. Assume that all M/M/s assumptions apply and there are 3 doctors available in the clinic. What is the average arrival rate if the units are in minutes?
30
45
0.5
1.25
0.8333
0.1389
0.5
When customers arrive independently of one another for a service, we can conclude that:
The service time is exponentially distributed
The queue size is limited
The time between arrivals will follow a normal distribution
The time between arrivals will follow an exponential distribution.
The time between arrivals will follow an exponential distribution.
The following is true about a forecast:
The forecast will always be equal to the actual demand
The forecast will be more accurate if the timeframe of the forecast is longer
None of the above
All of the above
None of the above
Customers arrive at a store (independently of one another) at a rate of 18 per hour. There is 1 server in the store. Service times are exponentially distributed averaging 5 minutes per customer. If all other M/M/s model assumptions apply, what would be the average service rate (per hour)?
:
6
18
3
5
120
12
12
A call canter expects an average of 560 calls during the 8 AM to 5 PM shift during which full time workers are employed. The average service time is 4 minutes per call. What is the minimum number of workers to achieve a capacity buffer not less than 10%.
5
6
more than 6
less than 5
5
The following is an assumption of the M/M/s queuing model:
Service times are normally distributed.
The queue length is limited to the size of the building.
Customer interarrival times (time between arrivals) are exponentially distributed.
All of the above
Customer interarrival times (time between arrivals) are exponentially distributed.
