TOM 301 Chapter 8 and 9 Practice Problems
Conceptual Question 8-11 Taiichi Ohno built... 14. Taiichi Ohno built the Toyota Production System with the metaphor of a tiger in mind. Rapid and decisive movements were his view the best way to match supply with demand. - True - False
- False Ohno had the slow but steady movement of the turtule (tortoise) in mind.
Conceptual Question 8-14 If the takt time... 17. If the takt time increases, the operation requires: - More workers - Fewer workers
- Fewer workers
Conceptual Question 9-7 If a process has... 30. If a process has a six sigma capability, what is the process capability index? - 1 - 2 - 6 - 12
- 2
Conceptual Question 9-8 For one and the same... 31. For one and the same process, what scenario corresponds to a higher variation? - A six sigma process - A three sigma process - Cannot be determined from the given information
- A three sigma process
Conceptual Question 8-20 A company makes... 22. A company makes two models, A and B. Which of the following production schedules is more level? - ABABABABAB - AAAAABBBBB
- ABABABABAB
Conceptual Question 8-9 What are the two pillars... 12. What are the two pillars of the Toyota Production System? - Just-in-Time and waste reduction - Waste reduction and built in quality - Built in quality and Just-in-Time - Process improvement and waste reduction
- Built in quality and Just-in-Time
Conceptual Question 8-13 If the demand rate... 16. If the demand rate increases, the takt time: - Increases - Decreases
- Decreases
10. In a service operation, we can compute the value add time by simply looking at the labor content. - True - False
- False
Conceptual Question 9-4 You harvest 50... 27. You harvest 50 tomatoes. You notice that the tomatoes vary in size and weight. If some of the tomatoes were exposed to extra sunshine or irrigation, this would be a common cause variation. - True - False
- False
Conceptual Question 8-8 A company is increasing... 11. A company is increasing the percentage value add time in the operation. Their value add time and their flow rate remain unchanged. What will happen to their inventory turns (recall from chapter 2 that inventory turns are computed as flow rate divided by inventory)? - Inventory turns will go up - Inventory turns will stay constant - Inventory turns will go down - Cannot determine from the given information
- Inventory turns will go up
Conceptual Question 9-5 You measure the exact... 28. You measure the exact size of 100 ping pong balls from manufacturer A and then another 100 balls of manufacturer B. The balls of manufacturer B have a much larger variation. Means and specification limits for the two manufacturers are identical. Which of the two manufacturers has a higher process capability index? - Manufacturer A - Manufacturer B - Cannot be determined from the given information
- Manufacturer A
Conceptual Question 8-19 Because of long set-up... 21. Because of long set-up times, a company chooses to run big production batches. Which of the following actions will level the production schedule? - Using overtime - Mixing the models on the final line - Making sure that rework is kept low - Reducing the waste of the process
- Mixing the models on the final line
4. An orthopedic surgeon read about TPS and wants to organize her surgery operation based on lean principles. To eliminate idle time in the operating room, she decides to call in patients six hours before the scheduled surgery time. Is this a lean process? - Yes - No - Cannot be determined
- No
8. An executive declares that his company has achieved an OEE of 115%. Is this possible? - Yes - No - Sometimes
- No
7.
- Non-value add time
9. Which of the following does not belong to the seven sources of waste? - Rework - Over time - Transportation - Inventory
- Over time
Conceptual Question 8-15 Which of the following... 18. Which of the following objectives is more important in a pull system? - Producing at the rate of demand - Keeping the equipment utilization
- Producing at the rate of demand
6. A worker in charge of assembling a bicycle finds a faster way to mount the pedals. He turns to his supervisor. The supervisor explains that the process had been optimized by the engineering department and so the worker should make sure to stick with the existing procedures. The work of which management scholar does this fit best? - Taylor - Ohno - Womack - Fujimoto
- Taylor
Conceptual Question 8-18 What happens to the... 20. What happens to the number of Kanban cards in the process if the replenishment time goes up? - The number of Kanban cards increases - The number of Kanban cards stays the same - The number of Kanban cards decreases - Cannot determine from the given information
- The number of Kanban cards increases
Conceptual Question 9-2 Mary and Tom operate... 25. Mary and Tom operate a lemonade stand. They are concerned that the lemonade does not taste fresh at the end of the day. Which of the following variables is an environmental variable in their operation? - The temperature of the lemonade when they take it out of their fridge in the morning - The temperature of the air during the day - The temperature of the lemonade - The temperature of the water used to make lemonade
- The temperature of the air during the day
Conceptual Question 9-1 In the production of pizza,... 24. In the production of pizza, which of the following four variables is not an input variable? - The amount of dough prepared for the pizza - The temperature of the oven - The type of cheese on the pizza - The time that the customer leaves the pizza in the fridge
- The time that the customer leaves the pizza in the fridge
Conceptual Question 8-16 What is the relationship... 19. What is the relationship between the number of Kanban cards in a process and the inventory level? - There is no relationship between the two - There never can be more inventory in the process than what was authorized via Kanban cards - The inventory of the process grows with the square root of the number of Kanban cards - The inventory of the process can be reduced by adding more Kanban cards
- There can never be more inventory in the process than what was authorized via Kanban cards
5. Which car company is most associated with the term lean operations? - General motors - Ford - Toyota - Honda
- Toyota
Conceptual Question 9-3 Following the announcement... 26. Following the annoucement of a major quality problem, the share price of a company falls substantially. This decrease is a result of assignable cause variation. - True - False
- True
Conceptual Question 8-12 If customers want... 15. If customers want to have 1000 units over 10 days, one should aim at producing 100 units per day instead of doing 111 units per day in the beginning and then having a little safety buffer at the end. - True - False
- True Reduce waste
Conceptual Question 8-10 What is the roof... 13. What is the roof in the "house-shaped" representation of the Toyota Production System? - Just-in-Time - Waste reduction - Built in quality - Process improvement
- Waste reduction
Conceptual Question 9-6 John is a newly minted... 29. John is a newly minted quality engineer at MakeStuff Inc. His boss tells him to increase the process capability index of their main product. John is somewhat lazy and so he does not want to tackle the variation in the process. So he decides to simply increase the upper specification limit and reduce the lower specification limit. Does this increase the process capability index? - No, it does not, as the variation in the process stays unchanged - Yes, it does though one might question if the underlying process is really better - That depends on many other variables, including control limits - No, the process capability index would only change if the control limits were changed
- Yes, it does, though one might question if the underlying process is really better
2. In the welding operations of a bicycle manufacturer, a bike frame has a flow time of about 14.5 hours. the time in the welding operation is spent as follows: 1 hour waiting in front of the cutting machine for the batch to start, 2 hours waiting for the setup of the machine, 2 hours waiting that the other pieces of the batch go through cutting, 1 minute at the cutting machine, and 3 hours waiting for the transfer to the welding machine. Then, at the welding machine, the unit spends 2 hours waiting in front of the welding machine for the batch to start, 2 hours waiting for the setup of the welding machine, 0.5 hours waiting that the other pieces of the batch go through cutting, 0.75 minutes at the welding machine, and 2 hours waiting for the transfer to the next department. Determine the exact flow time. What is the value-added percentage of the flow time?
Exact flow time = 1+2+2+3+2+2+0.5+2 hours + 1.75 minutes = 14.5 hours + 1.75 minutes = 871.75 minutes Value-added percentage = Value add time/Exact flow time = 1.75/871.75 = *0.0020*
3. The welding department supplies parts to the final assembly line. Management decides to implement a kanban system and has collected the following data: - The daily demand is 1700 units - The production lead time is 2 days - 2 day safety stock - One container fits 350 units How many kanban containers will be needed?
Kanban cards = [(production lead time x daily demand) + safety stock] / units per container = [(1700*2) + 1700*2] / 350 = 6800 / 350 = 19.4286 = *20*
1. A copy machine is available 24 hours a day. On a typical day, the machine produces 80 jobs. Each job takes about 2 minutes on the machine, 1 minute of which is processing time and 1 minute is setup time (logging in, defining the job). About 16% of the jobs need to be reworked, in which case the set-up time and the processing time have to be repeated. The other time, the equipment is idle. What is the OEE of the equipment?
OEE = Value add time / Total time = 80*1 / 24*60 = 80/1440 = 0.0555 = *5.6%*
PA 9-3 A company making tires for bikes is concerned... 23. A company making tires for bikes is concerned about the exact width of their cyclocross tires. The company has a lower specification limit of 22.6 mm and an upper specification limit of 23.2 mm. The standard deviation is 0.2 mm and the mean is 22.9 mm. What is the process capability index for the process?
PCI = (USL - LSL) / 6 x SD = (23.2 - 22.6) / 6 x 0.2 = *0.5000*
