Q&A Hero

Q: A waiting-line system that meets the assumptions of M/M/S has u03bb = 5, u03bc = 4, and M = 2. For these values, Po is approximately 0.23077 and Ls is approximately 2.05128. The average number of units waiting in the queue A) is approximately 0.1603 B) is approximately 0.4103 C) is approximately 0.8013 D) is approximately 1.0417 E) cannot be calculated because u03bb is larger than u03bc

Q: A waiting-line system that meets the assumptions of M/M/1 has u03bb = 1, u03bc = 4. For this system, Po is __________ and utilization is __________. A) 0.75; 0.25 B) 0.80; .20 C) -3; -4 D) 3; 4 E) none of these

Q: The basic form of cost-volume-profit analysis is often called break-even analysis.

Q: A waiting-line system that meets the assumptions of M/M/S has u03bb = 5, u03bc = 4, and M = 2. For these values, Po is approximately 0.23077 and Ls is approximately 2.05128. The average time a unit spends in this system A) is approximately 0.1603 B) is approximately 0.2083 C) is approximately 0.4103 D) is approximately 0.8013 E) cannot be calculated because u03bb is larger than u03bc

Q: 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. How many students, on the average, will be waiting in line at any one time? A) 0.9 students B) 1.5 students C) 3 students D) 4 students E) 36 students

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

Q: The high-low method is used to derive the variable cost per unit and total fixed costs using just the highest and lowest volume levels.

Q: A finite population waiting line model has an average service time T of 200 minutes and an average time between service requirements U of 300 minutes; the service factor X is A) 0.20 B) 0.40 C) 0.60 D) 0.67 E) 2.5

Q: 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 A) 0.20 B) 0.25 C) 4 D) 5 E) 300 minutes

Q: Scatter diagrams plot volume (units) on the vertical axis and cost on the horizontal axis.

Q: 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. What is the utilization factor? A) 20% B) 30% C) 40% D) 50% E) 60%

Q: A queuing model which follows the M/M/1 assumptions has u03bb = 2 and u03bc = 3. The average waiting time in the system is A) 2/3 B) 1 C) 1.5 D) 2 E) 6

Q: Four of the most widely used waiting line modelsM/M/1 or A, M/M/S or B, M/D/1 or C, and Limited population or Dall share three characteristics, which are A) normal arrivals, FIFO discipline, and normal service times B) Poisson arrivals, FIFO discipline, and a single-service phase C) Poisson arrivals, FIFO discipline, and exponential service times D) Poisson arrivals, no queue discipline, and exponential service times E) none of these

Q: A queuing model which follows the M/M/1 assumptions has u03bb = 2 and u03bc = 8. The average number in the system Ls is __________ and the utilization of the system is __________. A) 3; 100 percent B) 0.33; 25 percent C) 4; 33 percent D) 6; 25 percent E) 4; 25 percent

Q: The high-low method can be used to estimate the cost equation using just two points.

Q: A queuing model which follows the M/M/1 assumptions has u03bb = 10 and u03bc = 12. The average number in the system is A) 0.83 B) 2 C) 2.5 D) 5 E) 6

Q: 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. What is the average service time for this problem? A) 1 minute B) 2 minutes C) 3 minutes D) 5 minutes E) 20 minutes

Q: Least-squares regression is a statistical method for identifying cost behavior.

Q: A queuing model which follows the M/M/1 assumptions has u03bb = 3 and u03bc = 2. The average number in the system is A) -3 B) 3 C) 0.667 D) 150 percent E) growing without limit, since u03bb is larger than u03bc.

Q: A queuing model which follows the M/M/1 assumptions has u03bb = 2 and u03bc = 3. The average number in the system is A) 2/3 B) 1 C) 1.5 D) 2 E) 6

Q: 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) 2.25 B) 2.5 C) 3.0 D) 1.33 E) 5.0

Q: 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 length of the queue Lq is approximately A) 0.67 B) 2.5 C) 4.5 D) 5.0 E) 7.5

Q: The contribution margin ratio is the percent of each sales dollar that remains after deducting the total unit variable cost.

Q: Contribution margin per unit is the amount by which a product's unit selling price exceeds its total variable cost per unit.

Q: Which of the following is not an assumption of the M/M/1 model? A) The first customers to arrive are the first customers served. B) Each arrival comes independently of the arrival immediately before and after that arrival. C) The population from which the arrivals come is very large or infinite in size. D) Customers do not renege. E) Service times occur according to a normal curve.

Q: 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 A) 0.4 B) 0.133 C) 4.167 D) 4.583 E) 6

Q: In the basic queuing model (M/M/1), arrival rates are distributed by A) continuous probability distributions B) normal probability distributions C) negative exponential probability distributions D) Poisson distributions E) lognormal distributions

Q: In the basic queuing model (M/M/1), service times are described by A) binomial probability distributions B) negative exponential probability distributions C) Poisson probability distributions D) normal probability distributions E) lognormal distributions

Q: The dollar amount of sales needed to achieve a target income is computed by dividing the sum of fixed costs plus the target income by the contribution margin ratio.

Q: Which one of the following is not a characteristic of a Model C or M/D/1 system? A) single channel B) single phase C) Poisson arrival rate pattern D) exponential service time pattern E) unlimited population size

Q: Which one of the following is not a characteristic of a Model B or M/M/S system? A) unlimited population size B) single channel C) single queue D) single phase E) Poisson arrival rate pattern

Q: Cost-volume-profit analysis can be used to compute expected income from predicted sales and cost levels.

Q: Which one of the following is not a characteristic of a Model A or M/M/1 system? A) exponential service time pattern B) single number of channels C) single number of phases D) Poisson arrival rate pattern E) limited population size

Q: Cost-volume-profit analysis is used to predict future costs to be incurred, volumes of activity, sales to be made, and profit to be earned.

Q: As the average service rate u03bc increases, the shape of the negative exponential distribution of service times A) grows steadily steeper without limit B) has an ever steeper slope that eventually turns positive C) becomes less gently curved as it moves ever closer to the graph origin D) takes on a more uniform slope over a wide range of service times E) changes in appearance from convex to concave

Q: Cost-volume-profit analysis is a precise tool for determining the profit consequences of future cost changes, price changes, and volume of activity changes.

Q: A waiting line model meeting the assumptions of M/M/1 has an arrival rate of 2 per hour and a service rate of 6 per hour; the utilization factor for the system is approximately A) 0.25 B) 0.33 C) 0.50 D) 0.67 E) 3.00

Q: Cost-volume-profit analysis requires management to classify all costs as either fixed or variable with respect to production or sales volume within the relevant range of operations.

Q: 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) 0.25 B) 0.33 C) 0.50 D) 0.67 E) 3.00

Q: The relevant range of operations is a range of volume neither close to zero nor at maximum capacity.

Q: Which of the following is not a measure of a queue's performance? A) average time spent in queue B) average queue length C) probability that service facility will be idle D) utilization E) All of the above are performance measures.

Q: In a repetitive focus factory, the number of channels available for the processing of a certain part would likely refer to A) the number of successive operations that have to be performed on that part B) the number of machines doing the same necessary operations C) the number of parts waiting to be processed D) all of the above depending on the layout E) none of the above

Q: Curvilinear costs increase as volume of activity increases, but at a nonconstant rate.

Q: Which of the following is most likely to be served in a last-in, first-served (LIFS) queue discipline? A) customers checking out at a grocery store B) the in-basket on a manager's desk C) patients entering a hospital emergency room D) patrons waiting to be seated in a casual-dining restaurant E) all of the above

Q: Which of the following is a measure of queue performance? A) utilization factor B) average queue length C) probability of a specific number of customers in the system D) average waiting time in the line E) all of the above

Q: As the level of volume of activity increases, the variable cost per unit remains constant.

Q: In a repetitive focus factory, the number of phases found in the system might refer to 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) all of the above depending on the layout E) none of the above

Q: As the volume increases, fixed cost per unit of output remains constant.

Q: A system in which the customer receives service from only one station and then exits the system is A) a single-phase system B) a single channel system C) a multiple-channel system D) a multiple-phase system E) none of the above

Q: A university has several technicians in the repair station to care for the computers in the student labs. This system is most likely A) single channel, limited queue system B) single channel, limited population system C) multi-channel, limited queue system D) multi-channel, limited population system E) none of the above

Q: "Women and children first!" declares the captain of a sinking ship. His directive employs which of the following queue disciplines in disembarking passengers? A) priority B) random C) FIFO or FIFS D) LIFO or LIFS E) SPT

Q: Variable costs per unit increase proportionately with increases in volume of activity.

Q: A university has only one technician in the repair station to care for the computers in the student labs. This system is most likely A) a single channel, limited queue system B) a single channel, limited population system C) a multi-channel, limited queue system D) a multi-channel, limited population system E) none of the above

Q: Total variable costs change in proportion to changes in volume of activity.

Q: A large discount store and supermarket has a hair styling salon on its premises. The salon has several operators. Salon customers can shop in other parts of the store until their name is called for salon service, at which time the customer will be served by the next available stylist. This scenario provides an example of a A) multi-channel, limited queue length B) single-channel, multi-phase, limited queue length C) multi-channel, unlimited queue length D) multiple single-channel systems, limited queue length E) single-channel, unlimited queue length

Q: The ratio (proportion) of the sales volumes of the various products sold by a company is called the ______________________________.

Q: A small hair styling salon has several operators. While customers do not have appointments, each is waiting to be served by a specific operator. This scenario provides an example of a A) multiple-channel, multi-phase, limited queue length B) single-channel, multi-phase, limited queue length C) multi-channel, limited queue length D) multiple single-channel systems, limited queue length E) none of the above

Q: The sign at the bank that reads "Wait here for the first available teller" suggests the use of a __________ waiting line system. A) dynamic-channel B) random-channel C) single channel D) multi-channel E) multiple line

Q: If the food service for the university operates a cafeteria with a single serving line, that system behaves most like a A) single channel, single phase system B) single channel, multi-phase system C) multi-channel, single phase system D) multi-channel, multi-phase system E) none of the above

Q: A concert hall, employing both ticket takers and ushers to seat patrons, behaves typically as a A) multi-channel, single phase system B) multi-channel, multi-phase system C) single channel, single phase system D) single channel, multi-phase system E) none of the above

Q: _____________ is a statistical method of identifying an estimated line of cost behavior.

Q: An airline ticket counter, with several agents for one line of customers, is an example of a A) single channel, single phase system B) single channel, multi-phase system C) multi-channel, single phase system D) multi-channel, multi-phase system E) none of the above

Q: A college registrar's office requires you to first visit with one of three advisors and then with one of two financial professionals. This system is best described as A) single channel, single phase system B) single channel, multi-phase system C) multi-channel, single phase system D) multi-channel, multi-phase system E) multi-channel, cross-phase system

Q: Which of the following is most likely to violate a FIFO queue? A) supermarket with no express lanes B) car repair garage C) emergency room D) fast-food restaurant E) All of the above are equally likely to violate a FIFO queue.

Q: Which of the following represents an unlimited queue? 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

Q: Which of the following represents a customer that reneged due to the waiting-line? A) A husband and wife decide to eat out instead after seeing the movie ticket line. B) A car drives past the first fast-food restaurant on Hamburger Row because the drive-through was full. C) A Black Friday shopper skipped one store because the line went around the building. D) A student ordered pizza online because the phone line was busy. E) A customer at a gas station went inside to buy a soda, but after waiting in line for a minute left the soda behind and went outside empty-handed.

Q: Which of the following is an example of a finite arrival population? A) copy machines in a copying shop that break down B) students at a large university registering for classes C) shoppers arriving at a supermarket D) cars arriving at a suburban car wash E) all of the above

Q: Which part of a waiting line has characteristics that involve statistical distribution? A) arrivals or inputs B) waiting line itself C) service facility D) A and C E) A, B, and C

Q: Arrivals or inputs to a waiting-line system have characteristics that include A) population size B) population behavior C) population's statistical distribution D) A and C E) A, B, and C

Q: The potential restaurant customer who says to her husband, "The line looks too long; let's eat somewhere else," is an illustration of which element of queue discipline? A) first-in, first-out B) balk C) renege D) random departure E) none of the above

Q: The source population is considered to be either __________ in its size. A) finite or infinite B) fixed or variable C) known or unknown D) random or scheduled E) small or large

Q: A waiting line, or queuing, system has three parts, which are A) distribution of arrival times, discipline while waiting, and distribution of service times B) arrival rate, service rate, and utilization rate C) arrival discipline, queue discipline, and service sequencing D) arrival or inputs, queue discipline or the waiting line itself, and the service facility E) sequencing policy, penalty for reneging, and expediting of arrivals

Q: A _______________ cost is one that remains unchanged despite variations in the volume of activity within a relevant range. A ______________ cost is one that changes in proportion to changes in volume of activity.

Q: The shopper who says to himself, "I've waited too long in this line. I don't really need to buy this product today," and leaves the store is an illustration of which element of arrival behavior? A) random arrival B) renege C) random departure D) balk E) none of the above

Q: The common measures of a queuing system's performance include 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) none of the above

Q: Bing Company's contribution margin income statement is presented below. Sales for the current period consisted of 7,500 units. Compute the company's break-even point in (a) units, and (b) dollars. Compute the margin of safety in (c) dollars and (d) percent. Bing Company Contribution Margin Income Statement Sales $225,000 Variable costs 135,000 Contribution margin 90,000 Fixed costs 48,000 Net income $42,000

Q: In queuing problems, which of the following probability distributions is typically used to describe the time to perform the service? A) binomial B) normal C) Poisson D) negative exponential E) lognormal

Q: Dubashi Windows manufactures two standard size windows, J and R, in the ratio of 5:3. J has a selling price of $150 and R has a selling price of $200. The variable cost of J is $75.00 and the variable cost of R is $90.00. Fixed costs are $352,500. Compute the (a) weighted average contribution margin, (b) break-even point in units, (c) number of units of each product that will be sold at the break-even point.

Q: In queuing problems, which of the following probability distributions is typically used to describe the number of arrivals per unit of time? A) binomial B) normal C) Poisson D) exponential E) lognormal

Q: Magnolia Company is considering the production and sale of a new product with the following sales and cost data: unit sales price, $350; unit variable costs, $180; total fixed costs, $399,500; and projected sales, $910,000. Round your answers to the nearest whole unit or dollar. (a) Calculate break-even in units. (b) Calculate break-even in dollars (use four decimal places when calculating the contribution margin ratio). (c) Calculate number of units that would need to be sold to generate an after-tax profit of $420,000 assuming a 30% tax rate. (d) Calculate dollar sales that would be needed to generate the same profit as above. (e) Calculate the margin of safety stated as a percentage using the $910,000 projected sales level. Be sure to label each calculation and show all calculations.