Chapter 6

You are in a line at the bank drive-through and 4 cars are in front of you. You estimate that the clerk is taking about two minutes per car to serve. How long do you expect to wait in line?

8 minutes

Using the assembly-line balancing procedure, which of the following is the required cycle time in minutes per unit if the daily production time is 480 minutes and the required daily output is 50 units?

C = production time in one day / required output per day (in units) 480 minutes / 50 units = 9.6 minutes per unit

Which of the following is not a step in developing a manufacturing cell layout? a. Grouping parts into families that follow a common sequence of steps b. Identifying dominant flow patterns of parts families as a basis for location of processes c. Physically grouping machines and processes into cells d. Disposing of left-over machinery and outsourcing ungrouped processes e. None of the above

Disposing of left-over machinery and outsourcing ungrouped processes

Work center layouts allocate dissimilar machines into cells to work on products that have dissimilar processing requirements.

FALSE; A work center layout, sometimes referred to as a job shop, is where similar equipment or functions are grouped together.

A make-to-order firm will work with the customer to design the product, and then make it from purchased materials, parts, and components.

FALSE; Firms that make the customer's product from raw materials, parts, and components are make-to-order firms.

The closer the customer is to the customer order decoupling point the longer it takes the customer to receive the product.

FALSE; Selection of decoupling points is a strategic decision that determines customer lead times and can greatly impact inventory investment. The closer this point is to the customer, the quicker the customer can be served.

Using the assembly-line balancing procedure, which of the following is the theoretical minimum number of workstations if the task times for the six tasks that make up the job are 4, 6, 7, 2, 6, and 5 minutes, and the cycle time is 10 minutes?

Nt = Sum of task times / Cycle time, (4+ 6 +7 +2 + 6 +5)/10 = 3

A project layout is characterized by a relatively low number of units produced in comparison with process and product layout formats.

TRUE

Engineer-to-order firms will work with the customer to design the product, and then make it from purchased materials, parts, and components.

TRUE

One trade-off illustrated by the product-process matrix is between flexibility and cost.

TRUE

The term "assembly line" refers to progressive assembly linked by some material handling device.

TRUE

The Avis Company is a car rental company and is located three miles from the Los Angeles airport (LAX). Avis is dispatching a bus from its offices to the airport every 5 minutes. The average traveling time (a round trip) is 20 minutes. a. How many Avis buses are traveling to and from the airport? b. The branch manager wants to improve the service and suggests dispatching buses every 1.0 minute. She argues that this will reduce the average traveling time (a round trip) to 6.0 minutes. Is she correct? If your answer is negative, then what will the average traveling time be?

The throughput rate is 12 buses per hour. The throughput time is 20/60 = 0.3333 hourss Inventory = Throughput × Flow time = 12 × 0.3333 = 4 buses are traveling to and from the airport at any one time. b. This reduces the average waiting time, but has no effect on the average traveling time. The average traveling time does not change and will remain 20 min. This would however result in 20 buses being in transit between the airport and the office at any given time.

Safety regulations require that the time between airplane takeoffs (on the same runway) will be at least 2 minutes. When taking off, the run time of an airplane on the runway is 30 seconds. Planes are on average waiting 3 minutes and 18 seconds for take-off. On average there are 18 planes taking off per hour. How many planes are either on the runway or waiting to take off?

Throughput Rate = 18 planes per hour. Flow Time = (0.50 + 3.30)/60 = 5/79 of an hour. Inventory = Throughput Rate × Flow Time = 18 × 5/79 = 1.14 airplanes in line or taking off.

Which of the following is a basic type of process structure? a. Process flow diagram b. Product matrix c. Process matrix d. Workcenter e. Manual assembly

Workcenter