Question 1

Most banks have changed from having a line in front of each teller to a system where one line feeds all tellers. Which system is better? Why?

Accepted Answer

It is inherently mor

Question 2

A queuing model which follows the M/M/1 assumptions has λ = 2 and μ = 3. The average number in the system is

Accepted Answer

A)  2/3. 
B)  1. 
C)  1.5. 
D)  2. 
E)  6. 
A)  2/3. 
B)  1. 
C)  1.5. 
D)  2. 
E)  6.

Question 3

Students arrive randomly at the help desk of the computer lab. There is only one service agent, and the time required for inquiry varies from student to student. Arrival rates have been found to follow the Poisson distribution, and the service times follow the negative exponential distribution. The average arrival rate is 12 students per hour, and the average service rate is 20 students per hour. A student has just entered the system. How long is she expected to stay in the system?

Accepted Answer

A)  0.125 minute 
B)  0.9 minute 
C)  1.5 minutes 
D)  7.5 minutes 
E)  0.075 hour 
A)  0.125 minute 
B)  0.9 minute 
C)  1.5 minutes 
D)  7.5 minutes 
E)  0.075 hour

Question 4

A hospital emergency room always follows a first-in, first-served queue discipline in the interest of fairness.

Accepted Answer

A) True 
 B)False

Question 5

In an earlier chapter, you were introduced to a "traditional" view of costs and a "full cost" view of costs, with respect to a certain type of analysis. How might that lesson apply here? In particular, might operations managers pay more attention to some kinds of costs than others?

Accepted Answer

This is a critical-thinking exercise for

Question 6

A waiting line meeting the assumptions of M/M/1 has average time between arrivals of 20 minutes and services items in an average of 10 minutes each; the utilization factor is approximately

Accepted Answer

A)  0.25. 
B)  0.33. 
C)  0.50. 
D)  0.67. 
E)  3.00. 
A)  0.25. 
B)  0.33. 
C)  0.50. 
D)  0.67. 
E)  3.00.

Question 7

A waiting-line system that meets the assumptions of M/M/1 has = 1, = 4. Calculate Po. Build a table showing the probability of more than 0, 1, 2, 3, 4, 5, 6,and 7 units in the system. Round to six decimal places in your work

Accepted Answer

Question 8

A waiting line has a(n) ________ population if, as arrivals take place, the likelihood of additional arrivals is decreased.

Accepted Answer

The answer of A waiting line has a(n) ________ population...

Question 9

Which of the following represents an unlimited queue?

Accepted Answer

A)  drive-through lane at a fast-food restaurant 
B)  small barbershop with only 5 chairs for waiting customers 
C)  toll booth serving automobiles on an interstate 
D)  faculty office with limited seating during office hours 
E)  restaurant with no outside seating and limited capacity due to fire department restrictions 
A)  drive-through lane at a fast-food restaurant 
B)  small barbershop with only 5 chairs for waiting customers 
C)  toll booth serving automobiles on an interstate 
D)  faculty office with limited seating during office hours 
E)  restaurant with no outside seating and limited capacity due to fire department restrictions

Question 10

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 12 minutes on average. Service takes a constant 8 minutes. The average number in the system Ls is approximately

Accepted Answer

A)  2.25. 
B)  2.5. 
C)  3.0. 
D)  1.33. 
E)  5.0. 
A)  2.25. 
B)  2.5. 
C)  3.0. 
D)  1.33. 
E)  5.0.

Question 11

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 10 minutes on average. Service takes a constant 4 minutes. The average length of the queue Lq is

Accepted Answer

A)  0.4. 
B)  0.133. 
C)  4.167. 
D)  4.583. 
E)  6. 
A)  0.4. 
B)  0.133. 
C)  4.167. 
D)  4.583. 
E)  6.

Question 12

Suppose that customer arrivals are governed by a Poisson distribution. If the average arrival rate is 60 customers each hour, how many times will 60 customers arrive during a one hour period for each time that only 40 customers arrive.

Accepted Answer

P(60) = e^-60∗ 60⁶⁰/ 60! =

Question 13

A finite population waiting line model has an average service time T of 100 minutes and an average time between service requirements U of 400 minutes; the service factor X is 0.25.

Accepted Answer

A) True 
 B)False

Question 14

Balk and renege are elements of queue discipline.

Accepted Answer

A) True 
 B)False

Question 15

Suppose that 1 customer arrives each minute in a Poisson distribution. Is it more likely that 2 customers or 0 customers will arrive each minute?

Accepted Answer

P(0) = e^-1∗ 1⁰/0! = .368 P(2) = e

Question 16

As the average service rate μ grows larger, the slope of the distribution of service time probabilities grows larger and larger, eventually becoming positive.

Accepted Answer

A) True 
 B)False

Question 17

The common measures of a queuing system's performance include

Accepted Answer

A)  probability that the service facility will be idle, average queue length, probability that the waiting time will exceed a specified duration. 
B)  average time each customer spends in the system, probability that the service system will be idle, average time each customer spends in the queue. 
C)  average queue length, maximum time a customer may spend in the queue, the utilization factor for the system. 
D)  average time each customer spends in the system, maximum queue length, probability of a specific number of customers in the system. 
E)  average time that the service facility is idle, minimum queue length, probability that the waiting time will exceed a specified duration. 
A)  probability that the service facility will be idle, average queue length, probability that the waiting time will exceed a specified duration. 
B)  average time each customer spends in the system, probability that the service system will be idle, average time each customer spends in the queue. 
C)  average queue length, maximum time a customer may spend in the queue, the utilization factor for the system. 
D)  average time each customer spends in the system, maximum queue length, probability of a specific number of customers in the system. 
E)  average time that the service facility is idle, minimum queue length, probability that the waiting time will exceed a specified duration.

Question 18

A queuing model which follows the M/M/1 assumptions has λ = 2 and μ = 3. The average waiting time in the system is

Accepted Answer

A)  2/3. 
B)  1. 
C)  1.5. 
D)  2. 
E)  6. 
A)  2/3. 
B)  1. 
C)  1.5. 
D)  2. 
E)  6.

Question 19

In a repetitive focus factory, the number of phases found in the system might refer to

Accepted Answer

A)  the number of successive operations that have to be performed on a part. 
B)  the number of machines doing the same necessary operations. 
C)  the number of parts waiting to be processed. 
D)  the number of workers waiting to perform their task. 
E)  the number of units with defects requiring rework. 
A)  the number of successive operations that have to be performed on a part. 
B)  the number of machines doing the same necessary operations. 
C)  the number of parts waiting to be processed. 
D)  the number of workers waiting to perform their task. 
E)  the number of units with defects requiring rework.

Question 20

Which one of the following is not a characteristic of a Model C or M/D/1 system?

Accepted Answer

A)  single channel 
B)  single phase 
C)  Poisson arrival rate pattern 
D)  exponential service time pattern 
E)  unlimited population size 
A)  single channel 
B)  single phase 
C)  Poisson arrival rate pattern 
D)  exponential service time pattern 
E)  unlimited population size

Exam 21: Waiting-Line Models

Most banks have changed from having a line in front of each teller to a system where one line feeds all tellers. Which system is better? Why?

A queuing model which follows the M/M/1 assumptions has λ = 2 and μ = 3. The average number in the system is

A hospital emergency room always follows a first-in, first-served queue discipline in the interest of fairness.

In an earlier chapter, you were introduced to a "traditional" view of costs and a "full cost" view of costs, with respect to a certain type of analysis. How might that lesson apply here? In particular, might operations managers pay more attention to some kinds of costs than others?

A waiting line meeting the assumptions of M/M/1 has average time between arrivals of 20 minutes and services items in an average of 10 minutes each; the utilization factor is approximately

A waiting-line system that meets the assumptions of M/M/1 has = 1, = 4. Calculate Po. Build a table showing the probability of more than 0, 1, 2, 3, 4, 5, 6,and 7 units in the system. Round to six decimal places in your work

A waiting line has a(n) ________ population if, as arrivals take place, the likelihood of additional arrivals is decreased.

Which of the following represents an unlimited queue?

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 12 minutes on average. Service takes a constant 8 minutes. The average number in the system Ls is approximately

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 10 minutes on average. Service takes a constant 4 minutes. The average length of the queue Lq is

Suppose that customer arrivals are governed by a Poisson distribution. If the average arrival rate is 60 customers each hour, how many times will 60 customers arrive during a one hour period for each time that only 40 customers arrive.

A finite population waiting line model has an average service time T of 100 minutes and an average time between service requirements U of 400 minutes; the service factor X is 0.25.

Balk and renege are elements of queue discipline.

Suppose that 1 customer arrives each minute in a Poisson distribution. Is it more likely that 2 customers or 0 customers will arrive each minute?

As the average service rate μ grows larger, the slope of the distribution of service time probabilities grows larger and larger, eventually becoming positive.

The common measures of a queuing system's performance include

A queuing model which follows the M/M/1 assumptions has λ = 2 and μ = 3. The average waiting time in the system is

In a repetitive focus factory, the number of phases found in the system might refer to

Which one of the following is not a characteristic of a Model C or M/D/1 system?

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A waiting-line system that meets the assumptions of M/M/1 has = 1, = 4. Calculate P_o. Build a table showing the probability of more than 0, 1, 2, 3, 4, 5, 6,and 7 units in the system. Round to six decimal places in your work

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 12 minutes on average. Service takes a constant 8 minutes. The average number in the system L_s is approximately

A single-phase waiting-line system meets the assumptions of constant service time or M/D/1. Units arrive at this system every 10 minutes on average. Service takes a constant 4 minutes. The average length of the queue L_q is