SCM 300 Exam 2 (long) Questions with Correct Answers (Grade
A+)
Question 1: On average, how much time does the average customer spend in the SYSTEM when
there is ONE SERVER in the SYSTEM?
Answer: ts (minutes) = 3 minutes
Question 2: What percentage of the time would a server be busy in a FIVE-server model?
Answer: 12%
Question 3: What percentage of new arrivals are served immediately in a TWO-server model?
Answer: P0 + P1 .538 + .323 = .861 86.1%
Question 4: What is the probability in a single server model that at least one customer is in the
system?
Answer: RHO = 60%
Question 5: If one server can help 35 customers per hour and a new customer arrives every 4
minutes, then what percentage of the time would the server be busy?
Answer: 15 customers per hour (60 minutes / 4 minutes for a new customer) 15 customers per hour / 35
customers = .428 42.8%
Question 6: Goal of waiting line management
Answer: Finding the proper BALANCE between Long Lines Unhappy Customers Idle Staff High Cost
Question 7: Parts of a waiting line system
Answer: Input Source Waiting Line Service Facility
Question 8: Input Source
Answer: population of people that might want service
Question 9: Waiting Line
Answer: The area in which customers wait for service
Page 1
,Question 10: Service Facility
Answer: The area in which customers actually receive service
Question 11: 4 Managerial Considerations in Queues
Answer: 1) Customers - How many are there? How quickly are they arriving? 2) The Waiting Lines - What
types of lines? How many lines? 3) Employees - Who's working in the system? How many? Skill level and
speed? 4) Service Facilities - How effective and efficient is the process? Tools?
Question 12: Basic waiting line terminology
Answer: • Queue - Line. • Channel - Line. Here it often refers to the number of lines available at each step. •
Phase - A single step in a process. Example: Phases in college enrollment might include: Application
process, Registration, Orientation, Scheduling your courses for the first semester.
Question 13: Balking
Answer: When a potential customer sees the line, but never joins the line because they think it looks too
long or too slow.
Question 14: Reneging
Answer: When a customer joins the line, gets frustrated and leaves the line
Question 15: Arrival and Service Rates, Service Utilization Factor
Answer: What are they? Calculate them. Be able to read Arrival and Service Rates. Be able to covert to
/hour, per minute, and per second.
Question 16: Single Server Model
Answer: The simplest waiting line model involves a single server and a single line of customers
Question 17: Multiple Server Models
Answer: two or more independent servers in parallel serve a single waiting line
Question 18: Goals and Trade-Offs Queuing Systems
Answer: Sell, Deliver Value, Customer Satisfaction Trade offs - Having too many staff and underutilizing
them. OR too long a line, and angry customers. Both lose money Goal: To serve people efficiently.
Page 2
, Question 19: What do managers have control over in a queuing system?
Answer: -Time in system, time in queue, Service utilization, number of servers, what people do while in the
line, etc. -Have magazines, tv's, etc. Slow looking employees make wait time seem way longer. Some
customers are unprepared; others are ready when they get to the counter.
Question 20: Finite vs. Infinite Populations
Answer: FINITE Pool - Few potential customers. Every customer in the store significantly decreases the
chance of another customer arriving. Example: Retail store that sells jumbo jet airplanes. INFINITE Pool -
Many potential customers. Odds barely affected by new arrivals. Example: McDonald's (All our
calculations should be assumed to be infinite pools.)
Question 21: 4 Retailing Options
Answer: 1) Brick and Mortar - All products and services are sold to customers from physical stores.
Example: McDonald's 2) Online or E-tailing- All products and services are sold to customers through an
online website. Example: Amazon.com 3) Bricks and clicks - Products can be bought from a physical store
or from an online system. Example: Barnes and Noble and BN.com 4) Clicks and calls - In addition to
taking orders via the company website, some companies will also offer sales via the phone. Examples:
Lands' End and L.L. Bean
Question 22: Omni-channel retailing
Answer: Creating a seam-less cross-channel buying experience that integrates in- store, online, and mobile
shopping Ex. Nordstrom is a leader in omni-channel retailing
Question 23: 3 Retail sources of supply
Answer: 1) Manufacturers - These are the companies that actually create the finished goods. Retailers then
buy the goods and that retailer is responsible for distribution and storage. 2) Wholesalers - These
organizations purchase goods from manufacturers. Typically they purchase an assortment of goods from
many manufacturers, thus a retail company could purchase all of their electronics from a single wholesaler
versus having to purchase from each individual manufacturer. 3) Drop shippers - This one is not really a
source of supply, but rather an organization that ties manufacturers and/or wholesalers directly to
consumers.
Question 24: Chargebacks
Answer: financial penalties imposed on manufacturers by retailers
Page 3
A+)
Question 1: On average, how much time does the average customer spend in the SYSTEM when
there is ONE SERVER in the SYSTEM?
Answer: ts (minutes) = 3 minutes
Question 2: What percentage of the time would a server be busy in a FIVE-server model?
Answer: 12%
Question 3: What percentage of new arrivals are served immediately in a TWO-server model?
Answer: P0 + P1 .538 + .323 = .861 86.1%
Question 4: What is the probability in a single server model that at least one customer is in the
system?
Answer: RHO = 60%
Question 5: If one server can help 35 customers per hour and a new customer arrives every 4
minutes, then what percentage of the time would the server be busy?
Answer: 15 customers per hour (60 minutes / 4 minutes for a new customer) 15 customers per hour / 35
customers = .428 42.8%
Question 6: Goal of waiting line management
Answer: Finding the proper BALANCE between Long Lines Unhappy Customers Idle Staff High Cost
Question 7: Parts of a waiting line system
Answer: Input Source Waiting Line Service Facility
Question 8: Input Source
Answer: population of people that might want service
Question 9: Waiting Line
Answer: The area in which customers wait for service
Page 1
,Question 10: Service Facility
Answer: The area in which customers actually receive service
Question 11: 4 Managerial Considerations in Queues
Answer: 1) Customers - How many are there? How quickly are they arriving? 2) The Waiting Lines - What
types of lines? How many lines? 3) Employees - Who's working in the system? How many? Skill level and
speed? 4) Service Facilities - How effective and efficient is the process? Tools?
Question 12: Basic waiting line terminology
Answer: • Queue - Line. • Channel - Line. Here it often refers to the number of lines available at each step. •
Phase - A single step in a process. Example: Phases in college enrollment might include: Application
process, Registration, Orientation, Scheduling your courses for the first semester.
Question 13: Balking
Answer: When a potential customer sees the line, but never joins the line because they think it looks too
long or too slow.
Question 14: Reneging
Answer: When a customer joins the line, gets frustrated and leaves the line
Question 15: Arrival and Service Rates, Service Utilization Factor
Answer: What are they? Calculate them. Be able to read Arrival and Service Rates. Be able to covert to
/hour, per minute, and per second.
Question 16: Single Server Model
Answer: The simplest waiting line model involves a single server and a single line of customers
Question 17: Multiple Server Models
Answer: two or more independent servers in parallel serve a single waiting line
Question 18: Goals and Trade-Offs Queuing Systems
Answer: Sell, Deliver Value, Customer Satisfaction Trade offs - Having too many staff and underutilizing
them. OR too long a line, and angry customers. Both lose money Goal: To serve people efficiently.
Page 2
, Question 19: What do managers have control over in a queuing system?
Answer: -Time in system, time in queue, Service utilization, number of servers, what people do while in the
line, etc. -Have magazines, tv's, etc. Slow looking employees make wait time seem way longer. Some
customers are unprepared; others are ready when they get to the counter.
Question 20: Finite vs. Infinite Populations
Answer: FINITE Pool - Few potential customers. Every customer in the store significantly decreases the
chance of another customer arriving. Example: Retail store that sells jumbo jet airplanes. INFINITE Pool -
Many potential customers. Odds barely affected by new arrivals. Example: McDonald's (All our
calculations should be assumed to be infinite pools.)
Question 21: 4 Retailing Options
Answer: 1) Brick and Mortar - All products and services are sold to customers from physical stores.
Example: McDonald's 2) Online or E-tailing- All products and services are sold to customers through an
online website. Example: Amazon.com 3) Bricks and clicks - Products can be bought from a physical store
or from an online system. Example: Barnes and Noble and BN.com 4) Clicks and calls - In addition to
taking orders via the company website, some companies will also offer sales via the phone. Examples:
Lands' End and L.L. Bean
Question 22: Omni-channel retailing
Answer: Creating a seam-less cross-channel buying experience that integrates in- store, online, and mobile
shopping Ex. Nordstrom is a leader in omni-channel retailing
Question 23: 3 Retail sources of supply
Answer: 1) Manufacturers - These are the companies that actually create the finished goods. Retailers then
buy the goods and that retailer is responsible for distribution and storage. 2) Wholesalers - These
organizations purchase goods from manufacturers. Typically they purchase an assortment of goods from
many manufacturers, thus a retail company could purchase all of their electronics from a single wholesaler
versus having to purchase from each individual manufacturer. 3) Drop shippers - This one is not really a
source of supply, but rather an organization that ties manufacturers and/or wholesalers directly to
consumers.
Question 24: Chargebacks
Answer: financial penalties imposed on manufacturers by retailers
Page 3
