OM - CH 2 HW

LaVilla is a village in the Italian Alps. Given its enormous popularity among Swiss, German, Austrian, and Italian skiers, all of its beds are always booked in the winter season and there are, on average, 1,600 skiers in the village. On average, skiers stay in LaVilla for 9 days. How many new skiers are arriving, on average, in LaVilla every day?

1,600 beds divided by 9 days = 178 new skiers per day.

One of the chair lifts at a ski resort unloads 1,600 skiers per hour at the top of the slope. The ride from the bottom to the top takes 12 minutes. How many skiers are riding the lift at any given time?

1,600 skiers divided by 60 minutes per hour (flow rate) × 12 minutes (flow time) = 320 skiers

The table below provides the time stamps for the 8 people who called a reservation desk for a ferry service between 8:00 am and 8:30 am. Based on the data in the table, what is the flow rate of callers?

8 calls divided by 30 minutes = 0.3 calls per minute.

Forty customers per 90 minutes is a(n) ______

Flow rate

The table below shows the time stamps of 10 customers who visited a local bank branch from 9:00 a.m. to 9:45 a.m. What is the flow rate of customers?

Flow rate = 10 customers divided by 45 minutes = 0.2222.

CodeDeskInc matches programmers with freelance jobs. It has 35 employees who staff its online chat room. It receives, on average, 240 chat requests per hour, and the average chat session takes 5 minutes to complete (i.e., from start to finish). On average, how many chat sessions are active (i.e., started but not completed)?

Flow rate = 240 chats divided by 35 employees = 6.86 Flow time = 5 minutes divided by 60 minutes = 0.083 hour Inventory = Flow Rate × Flow Time, 6.86 × 0.083 = 0.5714 × 35 employees = 20 chats

Last year, there were 3,300,000 visitors to a national park and, on average, each visitor spent 20 hours in the park. Last year, on average, how many visitors were in the park?

Flow rate = 3,300,000 visitors divided by 365 days = 9,041 visitors per day Flow time = 20 hours / 24 hours per day = 0.8300 days Inventory = 9,041 (flow rate) × 0.8300 (flow time) = 7,534 visitors per day

Little's Law states there is a relationship between: (Choose all that apply) Inventory Flow time Output Throughput

Inventory Flow time Throughput

It is election day and 1800 voters vote in their precinct's library during the 10 hours the polls are open. On average, there are 15 voters in the library and they spend on average 5 minutes in the library to complete their voting. What is the inventory of voters, the flow rate, and the flow time for each voter?

Inventory of voters 15voters Flow rate 180per hour Flow time 5minutes The flow rate is 1,800 / 10 = 180 per hour, or 180 / 60 = 3 per minute. The flow time is 5 minutes.

If inventory is measured in kilograms, then when applying Little's Law the flow rate can be measured in ______

Kilograms / second

From the perspective of process analysis, which of the following could be appropriate flow units for a hardware store? Number of workers Number of cash registers Number of customers Number of suppliers

Number of customers The number of workers, cash registers, and suppliers are unlikely to change much over the course of a month and do not "flow" through the process of the hardware store.

For the purpose of process analysis, which of the following measures would be considered an appropriate flow unit for analyzing the operation of a coffee shop?

Number of customers served

Over the course of a month, which of the following is most likely to describe an appropriate flow unit for a process analysis of a hospital? The number of physicians The number of beds The square footage of the building The number of patients

The number of patients Physicians, beds, and square footage are unlikely to change much over the course of a month and do not "flow" through the process of a hospital.

The table below provides the time stamps for the 8 people who called a reservation desk for a ferry service between 8:00 am and 8:38 am. Based on the data in the table, what is the flow time of callers?

To calculate the flow time of the callers, subtract the callers departure time from his or her arrival time. 128 total minutes divided by 8 callers = 16.0 minutes.

For the purpose of process analysis, which of the following measures would be considered an appropriate flow unit for analyzing the main operation of a gas station? Sales dollars number of gasoline pumps number of employees number of customers served

sales dollars number of customers served

A Rhode Island company produces communion wafers for churches around the country and the world. The little company produces a lot of wafers, several hundred million per year. When in production, the process produces wafers at the rate of 123 per second. During this production process, the wafers must spend 15 minutes passing through a cooling tube.

123 per second × 60 seconds per minute × 15 minutes = 110,700

A consulting company must hire 18 new associates per year to replace those who have left the company for other positions or have retired. The company employs 131 associates overall. How long is the average associate employed at the consulting company?

18 associates = 131 new employees × flow time. Flow time = 7.3

A large-scale bakery is laying out a new production process for its packaged bread, which it sells to several grocery chains. It takes 11 minutes to bake the bread. How large of an oven is required so that the company is able to produce 4500 units of bread per hour (measured in the number of units that can be baked simultaneously)?

4,500 units divided by (11 minutes / 60 minutes) = 825 units

Patients take a drug for severe acne for 5 months and there are 60,000 new patients each month. How many patients are taking this drug on average at any given time?

5 months (flow time) × 60,000 new patients per month = 300,000 patients

Six customers enter a gift shop during a 3-hour period. On average there are 0.25 customers in the gift shop and each spends 7.5 minutes in the shop on average. Which of the following numbers is most directly associated with the flow rate of customers?

6 A rate is given in flow units per unit of time, as in six customers over 3-hours.

For the purpose of process analysis, which of the following measures would be considered an appropriate flow unit for analyzing the main operation of a local accounting firm? Number of accountants Number of tax returns completed Number of customers with past-due invoices Number of reams of paper received from suppliers

The *number of tax returns completed* reflects the main operation of the accounting firm during tax season. The accountants are resources; the customers with past-due invoices reflect the accounts receivable process and not the main operation; and the reams of paper received are a result of the firm's purchasing policies and not necessarily the main operation.

The table below shows the time stamps of 10 customers who visited a local bank branch from 9:00 a.m. to 10:00 a.m. What is the flow time of customers?

To calculate the flow time of the customers, subtract the customers departure time from his or her arrival time. 159 total minutes divided by 10 customers = 15.9 minutes.

A campus deli serves 350 customers over its busy lunch period from 11:30 a.m. to 1:30 p.m. A quick count of the number of customers waiting in line and being served by the sandwich makers shows that an average of 14 customers are in process at any point in time. What is the average amount of time that a customer spends in process?

To solve this problem, use Little's Law. Inventory = Flow rate × Flow time. 14 people in line (average inventory) = 2.9167 flow rate × flow time The flow rate is 350 customers divided by 120 minutes = 2.9167 customers/minute Flow time = 14 / 2.9167 = 4.8 minutes

Consider the baggage check-in process of a small airline. Check-in data indicate that from 9 a.m. to 10 a.m., 200 passengers checked in. Moreover, based on counting the number of passengers waiting in line, airport management found that the average number of passengers waiting for check-in was 29. How long did the average passenger have to wait in line?

To solve this problem, use Little's Law. Inventory = Flow rate × Flow time. 29 people in line (average inventory) = 200 customers / 60 minutes (flow rate) × flow time. Flow time = 8.7 minutes