Question 1

A multiple-channel system has more than one waiting line.

Accepted Answer

A) True 
 B)False

Question 2

When a waiting system is in steady-state operation, the number of units in the system is not changing.

Accepted Answer

A) True 
 B)False

Question 3

The postmaster at the Oak Hill Post Office expects the mean arrival rate of people to her customer counter will soon increase by fifty percent due to a large apartment complex being built. Currently, the mean arrival rate is 15 people per hour. The postmaster can serve an average of 25 people per hour. By what percentage must the postmaster's mean service rate increase when the apartment complex is completed in order that the average time spent at the post office remains at its current value?

Accepted Answer

The answer of The postmaster at the Oak Hill Post...

Question 4

​With no waiting allowed, operating characteristics Lq and Wq are automatically zero regardless of the number of servers.

Accepted Answer

A) True 
 B)False

Question 5

The assumption of exponentially distributed service times indicates that

Accepted Answer

A)  37% of the service times are less than the mean service time. 
B)  50% of the service times are less than the mean service time. 
C)  63% of the service times are less than the mean service time. 
D)  service time increase at an exponential rate as the waiting line grows. 
A)  37% of the service times are less than the mean service time. 
B)  50% of the service times are less than the mean service time. 
C)  63% of the service times are less than the mean service time. 
D)  service time increase at an exponential rate as the waiting line grows.

Question 6

​The equations provided in the textbook for computing operating characteristics apply to a waiting line operating

Accepted Answer

A)  ​at start-up. 
B)  ​at steady-state. 
C)  ​at peak-demand times. 
D)  ​in transition 
A)  ​at start-up. 
B)  ​at steady-state. 
C)  ​at peak-demand times. 
D)  ​in transition

Question 7

Queue discipline refers to the manner in which waiting units are arranged for service.

Accepted Answer

A) True 
 B)False

Question 8

Andy Archer, Ph.D., is a training consultant for six mid-sized manufacturing firms. On the average, each of his six clients calls him for consulting assistance once every 25 days. Andy typically spends an average of five days at the client's firm during each consultation.
Assuming that the time between client calls follows an exponential distribution, determine the following:
a.the average number of clients Andy has on backlog
b.the average time a client must wait before Andy arrives to it
c.the proportion of the time Andy is busy

Accepted Answer

a.L_q = .709

Question 9

In a waiting line situation, arrivals occur, on average, every 10 minutes, and 10 units can be received every hour. What are λ and μ?

Accepted Answer

A)  λ = 10, μ = 10 
B)  λ = 6, μ = 6 
C)  λ = 6, μ = 10 
D)  λ = 10, μ = 6 
A)  λ = 10, μ = 10 
B)  λ = 6, μ = 6 
C)  λ = 6, μ = 10 
D)  λ = 10, μ = 6

Question 10

The Arctic Flyers minor league hockey team has one box office clerk. On average, each customer that comes to see a game can be sold a ticket at the rate of 8 per minute. For normal games, customers arrive at the rate of 5 per minute. Assume arrivals follow the Poisson distribution and service times follow the exponential distribution.
a.What is the average number of customers waiting in line?
b.What is the average time a customer spends in the waiting line?
c.What is the average number of customers in the system?
d.What is a customer's average time in the system?
e.What is the probability that someone will be buying tickets when an arrival occurs?The Flyers are playing in the league playoffs and anticipate more fans, estimating that the arrival rate will increase to 12 per minute. Output is supplied for a two-cashier and a three-cashier system.   f. The rink has space for six customers to wait indoors to buy tickets. Which system will be better?g. Do you think it is more sensible for them to continue the one cashier system?

Accepted Answer

a.L_q = 1.04 B.W_q = .2083 C.L = 1.665 D.W =

Question 11

What queue discipline is assumed by the waiting line models presented in the textbook?

Accepted Answer

A)  first-come first-served. 
B)  last-in first-out. 
C)  shortest processing time first. 
D)  No discipline is assumed. 
A)  first-come first-served. 
B)  last-in first-out. 
C)  shortest processing time first. 
D)  No discipline is assumed.

Question 12

For all waiting lines, P0 + Pw = 1.

Accepted Answer

A) True 
 B)False

Question 13

Which of the following can NOT be found by the queuing formulas presented in the textbook?

Accepted Answer

A)  the probability that no units are in the system. 
B)  the average number of units in the system. 
C)  the maximum time a unit spends in the system. 
D)  the average time a unit spends in the system. 
A)  the probability that no units are in the system. 
B)  the average number of units in the system. 
C)  the maximum time a unit spends in the system. 
D)  the average time a unit spends in the system.

Question 14

Arrivals at a box office in the hour before the show follow the Poisson distribution with λ = 7 per minute. Service times are constant at 7.5 seconds. Find the average length of the waiting line.

Accepted Answer

The answer of Arrivals at a box office in the...

Question 15

For an M/M/1 queuing system, if the service rate, µ, is doubled, the average wait in the system, W, is cut in half.

Accepted Answer

A) True 
 B)False

Question 16

Quick Clean Rooter cleans out clogged drains. Due to the competitive nature of the drain cleaning business, if a customer calls Quick Clean and finds the line busy, they immediately try another company and Quick Clean loses the business.
Quick Clean management estimates that on the average, a customer tries to call Quick Clean every three minutes and the average time to take a service order is 200 seconds. The company wishes to hire enough operators so that at most 4% of its potential customers get the busy signal.
a.How many operators should be hired to meet this objective?
b.Given your answer to a), what is the probability that all the operators are idle?

Accepted Answer

a.k = 4; P

Question 17

The total cost for a waiting line does NOT specifically depend on

Accepted Answer

A)  the cost of waiting. 
B)  the cost of service. 
C)  the number of units in the system. 
D)  the cost of a lost customer. 
A)  the cost of waiting. 
B)  the cost of service. 
C)  the number of units in the system. 
D)  the cost of a lost customer.

Question 18

The 8 students in a seminar class must come to the professor's office to turn in a paper and give a 5-minute oral summary. Assume there is a service rate of 10 per hour and adequate time is available for all. The arrival rate for each unit is 5 per hour. What is the probability there is no one in the office or waiting when you come?

Accepted Answer

λ = 5, μ =

Question 19

In a waiting line situation, arrivals occur at a rate of 2 per minute, and the service times average 18 seconds. Assume the Poisson and exponential distributions.
a.What is λ?
b.What is μ?
c.Find probability of no units in the system.
d.Find average number of units in the system.
e.Find average time in the waiting line.
f. Find average time in the system.
g. Find probability that there is one person waiting.
h. Find probability an arrival will have to wait.

Accepted Answer

a.λ = 3/min. B.μ = 4/min. C.P₀

Question 20

For an M/M/k system, the average number of customers in the system equals the customer arrival rate times the average time a customer spends waiting in the system.

Accepted Answer

A) True 
 B)False

A multiple-channel system has more than one waiting line.

When a waiting system is in steady-state operation, the number of units in the system is not changing.

With no waiting allowed, operating characteristics L_q and W_q are automatically zero regardless of the number of servers.

The assumption of exponentially distributed service times indicates that

The equations provided in the textbook for computing operating characteristics apply to a waiting line operating

Queue discipline refers to the manner in which waiting units are arranged for service.

In a waiting line situation, arrivals occur, on average, every 10 minutes, and 10 units can be received every hour. What are λ and μ?

What queue discipline is assumed by the waiting line models presented in the textbook?

For all waiting lines, P₀ + P_w = 1.

Which of the following can NOT be found by the queuing formulas presented in the textbook?

Arrivals at a box office in the hour before the show follow the Poisson distribution with λ = 7 per minute. Service times are constant at 7.5 seconds. Find the average length of the waiting line.

For an M/M/1 queuing system, if the service rate, µ, is doubled, the average wait in the system, W, is cut in half.

The total cost for a waiting line does NOT specifically depend on

For an M/M/k system, the average number of customers in the system equals the customer arrival rate times the average time a customer spends waiting in the system.

Introduction

An Introduction to Linear Programming

Linear Programming: Sensitivity Analysis and Interpretation of Solution

Linear Programming Applications in Marketing, Finance, and Operations Management

Advanced Linear Programming Applications

Distribution and Network Models

Integer Linear Programming

Nonlinear Optimization Models

Project Scheduling: Pertcpm

Inventory Models

Simulation

Decision Analysis

Multicriteria Decisions

Time Series Analysis and Forecasting

Markov Processes

Linear Programming: Simplex Method

Simplex-Based Sensitivity Analysis and Duality

Solution Procedures for Transportation and Assignment Problems

Minimal Spanning Tree

Dynamic Programming

Filters

Exam 11: Waiting Line Models

A multiple-channel system has more than one waiting line.

When a waiting system is in steady-state operation, the number of units in the system is not changing.

​With no waiting allowed, operating characteristics Lq and Wq are automatically zero regardless of the number of servers.

The assumption of exponentially distributed service times indicates that

​The equations provided in the textbook for computing operating characteristics apply to a waiting line operating

Queue discipline refers to the manner in which waiting units are arranged for service.

In a waiting line situation, arrivals occur, on average, every 10 minutes, and 10 units can be received every hour. What are λ and μ?

What queue discipline is assumed by the waiting line models presented in the textbook?

For all waiting lines, P0 + Pw = 1.

Which of the following can NOT be found by the queuing formulas presented in the textbook?

Arrivals at a box office in the hour before the show follow the Poisson distribution with λ = 7 per minute. Service times are constant at 7.5 seconds. Find the average length of the waiting line.

For an M/M/1 queuing system, if the service rate, µ, is doubled, the average wait in the system, W, is cut in half.

The total cost for a waiting line does NOT specifically depend on

For an M/M/k system, the average number of customers in the system equals the customer arrival rate times the average time a customer spends waiting in the system.

Introduction

An Introduction to Linear Programming

Linear Programming: Sensitivity Analysis and Interpretation of Solution

Linear Programming Applications in Marketing, Finance, and Operations Management

Advanced Linear Programming Applications

Distribution and Network Models

Integer Linear Programming

Nonlinear Optimization Models

Project Scheduling: Pertcpm

Inventory Models

Simulation

Decision Analysis

Multicriteria Decisions

Time Series Analysis and Forecasting

Markov Processes

Linear Programming: Simplex Method

Simplex-Based Sensitivity Analysis and Duality

Solution Procedures for Transportation and Assignment Problems

Minimal Spanning Tree

Dynamic Programming

Filters

With no waiting allowed, operating characteristics L_q and W_q are automatically zero regardless of the number of servers.

The equations provided in the textbook for computing operating characteristics apply to a waiting line operating

For all waiting lines, P₀ + P_w = 1.