Practical Management Science
6th Edition
ISBN: 9781337406659
Author: WINSTON, Wayne L.
Publisher: Cengage,
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 6.5, Problem 33P
Summary Introduction
To modify: The model and find the optimal solution using solver.
Introduction: The variation between the present value of the
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
An emergency room (ER) at a Prisma Health Hospital has 10 total
beds it can hold patients, i.e., the capacity of the queueing system of this ER is 10. Patients
arrive to the ER at a rate of 5 per hour. Therefore, we have that λn = 6 for n = 0, 1, . . . , 9
and λ10 = 0 for this queueing system. A patient is seen by an ER doctor as the ‘service’
of this queueing system. The amount of time required for an ER doctor to treat a patient
is exponentially distributed with a mean of .4 hours. We seek the minimum number of ER
doctors so that the expected time of a patient waiting to be seen (so the Wq) is less than
or equal to 15 minutes (.25 hours). You should begin by analyzing s = 1 and show any
calculations that were used to determine Wq for each number of servers that you considered
until you meet the target metric.
Consider a bank with two tellers. Service times by each teller are exponentially distributed withmean of 1 hour per customer. Customers also arrive with an exponential interarrival times withmean of 1 hour. Suppose a customer has just arrived at 2pm:a. What is the probability that the next customer will arrive between 3:00 pm and 4:00 pm?b. If no customer arrives before 4:00 pm, what is the probability that the next customer willarrive between 4:00 pm and 5:00 pm?c. What is the probability that the number of arrivals between 2:00 pm and 4:00 pm will be morethan one?
MacBurger’s is attempting to determine how manyservers (or lines) should be available during the breakfastshift. During each hour, an average of 100 customers arriveat the restaurant. Each line or server can handle an averageof 50 customers per hour. A server costs $5 per hour, andthe cost of a customer waiting in line for 1 hour is $20.Assuming that an M/M/s/GD/∞/∞ model is applicable,determine the number of lines that minimizes the sum ofdelay and service costs.
Chapter 6 Solutions
Practical Management Science
Ch. 6.3 - Prob. 1PCh. 6.3 - Prob. 2PCh. 6.3 - Solve Problem 1 with the extra assumption that the...Ch. 6.3 - Prob. 4PCh. 6.3 - Prob. 5PCh. 6.3 - Prob. 6PCh. 6.3 - Prob. 7PCh. 6.3 - Prob. 8PCh. 6.3 - Prob. 9PCh. 6.3 - Prob. 10P
Ch. 6.4 - Prob. 11PCh. 6.4 - Prob. 12PCh. 6.4 - Prob. 13PCh. 6.4 - Prob. 14PCh. 6.4 - Prob. 15PCh. 6.4 - Prob. 16PCh. 6.4 - Prob. 17PCh. 6.4 - Prob. 18PCh. 6.4 - Prob. 19PCh. 6.4 - Prob. 20PCh. 6.4 - Prob. 21PCh. 6.4 - Prob. 22PCh. 6.4 - Prob. 23PCh. 6.5 - Prob. 24PCh. 6.5 - Prob. 25PCh. 6.5 - Prob. 26PCh. 6.5 - Prob. 28PCh. 6.5 - Prob. 29PCh. 6.5 - Prob. 30PCh. 6.5 - In the optimal solution to the Green Grass...Ch. 6.5 - Prob. 32PCh. 6.5 - Prob. 33PCh. 6.5 - Prob. 34PCh. 6.5 - Prob. 35PCh. 6.6 - Prob. 36PCh. 6.6 - Prob. 37PCh. 6.6 - Prob. 38PCh. 6 - Prob. 39PCh. 6 - Prob. 40PCh. 6 - Prob. 41PCh. 6 - Prob. 42PCh. 6 - Prob. 43PCh. 6 - Prob. 44PCh. 6 - Prob. 45PCh. 6 - Prob. 46PCh. 6 - Prob. 47PCh. 6 - Prob. 48PCh. 6 - Prob. 49PCh. 6 - Prob. 50PCh. 6 - Prob. 51PCh. 6 - Prob. 52PCh. 6 - Prob. 53PCh. 6 - Prob. 54PCh. 6 - Prob. 55PCh. 6 - Prob. 56PCh. 6 - Prob. 57PCh. 6 - Prob. 58PCh. 6 - Prob. 59PCh. 6 - Prob. 60PCh. 6 - Prob. 61PCh. 6 - Prob. 62PCh. 6 - Prob. 63PCh. 6 - Prob. 64PCh. 6 - Prob. 65PCh. 6 - Prob. 66PCh. 6 - Prob. 67PCh. 6 - Prob. 68PCh. 6 - Prob. 69PCh. 6 - Prob. 70PCh. 6 - Prob. 71PCh. 6 - Prob. 72PCh. 6 - Prob. 73PCh. 6 - Prob. 74PCh. 6 - Prob. 75PCh. 6 - Prob. 76PCh. 6 - Prob. 77PCh. 6 - Prob. 78PCh. 6 - Prob. 79PCh. 6 - Prob. 80PCh. 6 - Prob. 81PCh. 6 - Prob. 82PCh. 6 - Prob. 83PCh. 6 - Prob. 84PCh. 6 - Prob. 85PCh. 6 - Prob. 86PCh. 6 - Prob. 87PCh. 6 - Prob. 88PCh. 6 - Prob. 89PCh. 6 - Prob. 90PCh. 6 - Prob. 91PCh. 6 - Prob. 92PCh. 6 - This problem is based on Motorolas online method...Ch. 6 - Prob. 94PCh. 6 - Prob. 95PCh. 6 - Prob. 96PCh. 6 - Prob. 97PCh. 6 - Prob. 98PCh. 6 - Prob. 99PCh. 6 - Prob. 100PCh. 6 - Prob. 1CCh. 6 - Prob. 2CCh. 6 - Prob. 3.1CCh. 6 - Prob. 3.2CCh. 6 - Prob. 3.3CCh. 6 - Prob. 3.4CCh. 6 - Prob. 3.5CCh. 6 - Prob. 3.6C
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, operations-management and related others by exploring similar questions and additional content below.Similar questions
- An M/M/1 queueing system has that customers arrive to it at a rate of 5 per hour, i.e., its interarrival times between two consecutive arrivals follows an exponential distribution with parameter 5 per hour. This question will ask you to evaluate two options for designing the server in the system. Both options for the single server provide the same service for the customers in the queueing system but they cost different amounts to implement. In addition, the total costs of the queuing system are the implementation costs plus the customer costs. Currently, the customer costs are $100 per hour per customer in the queueing system. In comparing these options, it costs us $100 per hour per customer in the queueing system. (a) The first option for the server is one that has a service time that follows an exponential distribution with mean 10 minutes. Determine L, W, Lq, and Wq for this system. (b) The second option for the server is one that has a service time that follows an…arrow_forwardBased on Quinn et al. (1991). Winter Riggers handles approximately $400 million in telephone orders per year. Winter Riggers’ system works as follows. Callers are connected to an agent if one is available. Otherwise, they are put on hold (if a trunk line is available). A customer can hang up at any time and leave the system. Winter Riggers would like to efficiently manage the telephone system (lines and agents) used to process these orders. Of course, orders are very seasonal and depend on the time of day. a. What decisions must Winter Riggers make? b. What would be an appropriate objective for Winter Riggers to minimize (or maximize)? What difficulties do you see in specifying the objective? c. What data would Winter Riggers need to keep track of to improve its efficiency?arrow_forwardCPU-on-Demand (CPUD) offers real-time high-performance computing services. CPUD owns 1 supercomputer that can be accessed through the Internet. Their customers send jobs that arrive, on average, every 5 hours. The standard deviation of the interarrival times is 5 hours. Executing each job takes on average 3 hours on the supercomputer and the standard deviation of the processing time is 4.5 hours. How long does a customer have to wait to have a job completed?arrow_forward
- Consider a Poisson queue with the following steady-state probabilities: po = 1/3, p1 = 1/2, p2 = 1/6, and pn = for n = 3,4,5, ... . What is the minimum number of stools that would accommodate all customers in the system at least 75% of the time in steady state? 3 stools O 2 stools none of the other choices O 1 stoolarrow_forwardFood Goblin Supermarkets use both cashiers and baggers to serve customers at check out. During the peak hours, 8 cashiers and 6 baggers serve approximately 75 customers per hour. On average, a cashier spends 6 minutes at checkout and a bagger spends 4 minutes at bagging to serve a customer. Calculate the utilization of cashiers and their capacity cushion during a peak hour. Calculate the utilization of baggers and their capacity cushion during a peak hour. Calculate the overall average utilization of cashiers and baggers during a peak hour.arrow_forwardIn a service facility, a manager wants to find “Optimal Service Level” by employing a trade-off graph (a graph of costs vs level of services) between waiting costs and service costs. Describe and show the optimal service level on this grapharrow_forward
- During an eight-hour shift, 750 non-defective parts are desired as a result of a manufacturing operation. The default operation time is 15 minutes. As the operators of machine are inexperienced, the actual time they take to perform the operation is 20 minutes, and, on average, a fifth of the parts that start to be manufactured are lost. Assuming that each one of the machines used in this operation will not be available for one hour in each shift, determine the number of machines needed.arrow_forwardThe Decision Sciences Department is tyring to determine whether to rent a slow or fast copier. The department believes that an employee's time is worth $15/hour. The slow copier rents for $4/hr, and it takes an employee an average of 10 minutes to complete copying. The fast copier rents for $15/hr, and it takes an employee an average of 6 minutes to complete copying. On average, four employees per hour need to use the copying machine. (Assume the copying times and interarrival times to the copying machine are exponentially distributed.) Which machine should the department rent to minimize expected total cost per hour? Please note this class revolves around Microsoft Excel so the answer I need needs to show the formulas in Excel, along with any corresponding graphs, etc. Thank you in advance!arrow_forwardDr. Tarun Gupta, a Michigan vet, is running a rabies vaccination clinic for dogs at the local grade school. Tarun can "shoot" a dog every 3 minutes. It is estimated that the dogs will arrive independently and randomly throughout the day at a rate of one dog every 6 minutes according to a Poisson distribution. Also assume that Tarun's shooting times are negative exponentially distributed. a) The probability that Tarun is idle =arrow_forward
- What factors determine whether a person chooses car or bus to travel to work? That is an interesting question. Suppose that you analyze this simple transportation problem using the probit model. The variables in the model are defined as follows: autotime commute time via auto, minutes commute time via bus, minutes =(bus time - auto time)/10, 10 minute units = 1 if auto chosen bustime dtime auto The probit model you estimate is P(AUTO = 1) = ¤(ß1 + B2DTIME). The estimates of the parameters are: -0.0788 + 0.400DTIME. The marginal effect of increasing public (bus) transportation time, given that travel via public transportation currently takes 15 minutes longer than auto travel is A) 0.348 B) 0.139 C) 0.307 D) 0.123 E) None of the above (A, B, C, D) is close to be correct.arrow_forwardApproximately 40 percent of a medical clinic’s weekly incoming calls for doctors’ appointments occur on Monday. Due to this large workload, 20 percent of the callers receive a busy signal and have to call back later. The clinic has one clerk for each two departments to handle incoming calls. Each clerk handles calls for the same departments all week and thus is familiar with the doctors’ hours, scheduling practices, and idiosyncrasies. Consider the following alternatives to solve thi problem: ∙ Continue the present system, which results in some customer inconvenience, loss of business, and perceived poor service. About 1000 patients attempt to call the clinic on Mondays. The clinic has 50,000 patients in all. ∙ Expand the phone lines and add more people to handle the peak load. The estimated cost for adding two more lines and two clerks is $60,000 per year. ∙ Install a computer to speed up appointments. In this case, the peak load could be handled with the current personnel. The…arrow_forwardA college student works in both the school cafeteria and library. She works no more than 12 hours per week at the cafeteria, and no more than 16 hours per week at the library. She must work at least 20 hours each week. Write a system of inequalities that describes all the given conditions. Write a system of inequalities letting x= number of hours worked at the cafeteria per week and y = number of hours worked at the library per week. x+yz x≤ ysarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Practical Management ScienceOperations ManagementISBN:9781337406659Author:WINSTON, Wayne L.Publisher:Cengage,
Practical Management Science
Operations Management
ISBN:9781337406659
Author:WINSTON, Wayne L.
Publisher:Cengage,