Spreadsheet Modeling & Decision Analysis: A Practical Introduction To Business Analytics, Loose-leaf Version
8th Edition
ISBN: 9781337274852
Author: Ragsdale, Cliff
Publisher: South-Western College Pub
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Robert Olney's Barbershop is a popular haircutting and styling salon near the campus of the University of New Haven. Four barbers work full-time and
spend an average of 15 minutes on each customer. Customers arrive all day long at an average rate of 12 per hour. Arrivals tend to follow the
Poisson distribution, and service times are negative exponentially distributed. The software described in this quantitative module may be used to answer
the following questions.
a) The probability that the shop is empty is
b) The average number of customers in the barber shop is
c) The average time spent in the shop is
hours (round your response to three decimal places).
d) The average time that a customer waits to be called to the barber chair is hours (round your response to three decimal places).
e) The average number waiting to be served is
customers (round your response to two decimal places).
f) Robert is thinking of adding a fifth barber. The utilization rate of his shop will be (round your…
Note: Formulas to solve the following problems are given in the
class and example problems were solved in the class. Follow the
examples described in the class and read the literature posted on
blackboard.
1. Huntsville Bank (a fictitious one) has a drive-through teller
window and observed that customers arrive for service one
every three minute, on an average, and the average service
time per customer is 2.4 minutes. Assume inter-arrival time
and service time follow a negative Exponential distribution.
The bank hires you as a consultant. You guess that this is an
M|M|1 system and you are required to determine the
following:
a. Probability (teller is busy)
b. Probability (teller is idle)
c. Average number of customers waiting for service, that is,
number of autos in the line excluding the one at the teller
window.
d. Average number of customers in the system, that is,
number of autos in the line including the one at the teller
window.
e. Average time a customer spends in the waiting…
Tony’s Barbershop is run, owned, and operated by Anthony Jones, who has been cutting hairfor more than 20 years. Anthony does not take appointments, so the arrival pattern of customers is essentially random. Traditionally, the arrival rate had been about one customer every50 minutes. Two months ago, the local paper ran an article about Anthony that improved business substantially. Currently, the arrival rate is closer to one customer every 35 minutes. Haircutsrequire an average of 25 minutes, but the times vary considerably depending on customerneeds. A trim might require as little as 5 minutes, but a shampoo and styling could take as longas an hour or more. For this reason, the exponential distribution seems to provide a reasonablygood fit of the service time distribution.Anthony’s customers have always been patient, but ever since business picked up, somehave complained that the wait is too long. Anthony is considering taking his cousin Marvin intothe business to improve customer…
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The company’s services also include cost-effective ground delivery for parcels and extra-speedy same-day delivery for urgent deliveries within 1,800 cities. Over the years, FedEx has widened its delivery network to more than 220 countries. It has purchased more cargo jets and acquired specialized shipping firms, including Tiger International, Roberts Express, RPS, and TNT Express, to support global growth. For international business customers needing products, parts, or raw materials shipped across countries or continents, the company now offers time-saving services such as commercial freight forwarding and cross-border logistical support. To add the convenience of local drop-off and pickup points for U.S. consumers and small businesses, FedEx acquired the Kinko’s office services company in 2004 and later rebranded it as FedEx Office. This acquisition also added printing and copying to the menu of services offered. Then the company arranged for large U.S. retailers such as Walgreens, Albertsons, Kroger, and Safeway to accept packages for shipment and receive package delivery for customer pickup in thousands of store locations. This means people who want to send a package can head to a nearby retailer and ship where they shop, rather than making a separate trip to the FedEx location. It’s also a safe alternative for packages to be picked up by people who don’t want FedEx shipments left by the front door. Another service FedEx offers to small and mid-sized businesses, including retailers, is FedEx Fulfillment. The purpose is to expedite order fulfillment by having each business store its products in a FedEx warehouse. Then, when the business’s customers place orders, FedEx puts the products into boxes bearing the business’s own logo and ships directly to those customers. The business doesn’t need a separate warehouse or staff for fulfillment, and packages are on their way to customers more quickly because the products were in FedEx’s warehouse, ready to be packed and shipped. This service puts FedEx into direct competition with Amazon.com, which offers a similar service to merchants that sell through the online Amazon Marketplace. But it also gives businesses that don’t sell via Amazon a fast and professional fulfillment alternative. FedEx is careful to let customers know, through media and social-media announcements, when it anticipates that extreme weather or other conditions will cause delays or force it to halt pickups and deliveries. For the duration of Hurricane Irma, for example, FedEx said it would suspend deliveries in Florida. Some Florida customers who had ordered generators to be delivered via FedEx were unhappy, because they worried about being without power during and after the storm. But one FedEx employee loaded several generator orders into his car and took them to customers himself. When a customer posted a grateful compliment to FedEx on Facebook, the message generated thousands of likes, shares, and positive comments. The company also received positive comments for its donations of cash and transportation services to areas devastated by Hurricanes Irma, Harvey, and Maria. According to the American Customer Satisfaction Index (ACSI), FedEx often tops the list of U.S. shipping companies as ranked by customers surveyed. Every day, the company delivers 13 million packages—and during the busy year-end holiday season, it delivers many more. By meeting customers’ expectations for on-time deliveries, FedEx has increased annual revenues beyond $60 billion and positioned itself for continued growth in the future. How does FedEx’s money-back guarantee address customers’ concerns about heterogeneity?arrow_forwardMarty's Barber Shop has one barber. 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