Q&A Hero

Q: Breakdown maintenance is _____________; preventive maintenance is _________. A. reactive; proactive B. proactive; reactive C. expensive; inexpensive D. inexpensive; expensive E. easy; hard

Q: Maintenance activities are often organized into the following two groups: A. breakdown maintenance and preventive maintenance B. breakdown maintenance and predictive maintenance C. preventive maintenance and predictive maintenance D. equipment maintenance and breakdown maintenance E. equipment maintenance and buildings maintenance

Q: A. Every .67 weeks B. Every .33 weeks C. Every 2.67 weeks D. Every 3.25 weeks E. Every 3.12 weeks The z value associated with a cumulative probability of .667 is approximately .43. Multiply this by the standard deviation, then add to the mean.

Q: Suppose that for a particular piece of machinery, the frequency distribution of monthly breakdowns is as follows: The cost of a breakdown is $2,000, and the cost of a preventive maintenance program is $2,000 per month. If the preventive maintenance program is adopted, the probability of a machine breakdown is negligible. How much better off per month would the firm be if it adopted preventive maintenance? A. $100 worse off B. $200 worse off C. $100 better off D. $200 better off E. $2,000 better off

Q: Suppose that for a particular piece of machinery, the frequency distribution of monthly breakdowns is as follows: The cost of a breakdown is $2,000, and the cost of a preventive maintenance program is $2,000 per month. If the preventive maintenance program is adopted, the probability of a machine breakdown is negligible. How much better off per month would the firm be if it adopted preventive maintenance? A. $100 worse off B. $200 worse off C. $100 better off D. $200 better off E. $2,000 better off

Q: As a piece of equipment begins to break down more often, the manager is often faced with a trade-off in which __________ are weighed against the __________. A. failure rates; maintenance probabilities B. maintenance intervals; maintenance programs C. operating costs; variable costs D. replacement costs; continued maintenance costs E. fixed costs; maintenance costs

Q: In the area of maintenance, the Pareto phenomenon is reflected in the fact that, regardless of problem classification, all equipment will justify about the same expense.

Q: Pareto analysis (using the 80/20 rule) is one method of determining when preventive maintenance activities should be performed.

Q: In the broadest sense, preventive maintenance extends back to the installation stage of equipment and facilities.

Q: Ideally, preventive maintenance will be performed before a breakdown or failure.

Q: One basis for scheduling preventive maintenance is passage of time.

Q: Breakdown maintenance is best performed on a regularly scheduled basis.

Q: Degree of technology is a factor affecting the decision of how much preventive maintenance is desirable.

Q: Breakdown maintenance includes activities such as equipment inspection and adjustment.

Q: The goal of maintenance is to maintain the productive system in good working order while minimizing or eliminating the cost of preventive maintenance.

Q: The goal of maintenance is to minimize cost.

Q: If the value for average outgoing quality increases, this means that __________ defective units are being passed on.

Q: Suppose a batch is of unacceptable quality. There is a 10 percent chance that it will be accepted. Thus, ________ is 10 percent.

Q: Suppose a batch is of acceptable quality. There is a 10 percent chance that it will be rejected. Thus, ________ is 10 percent.

Q: A firm uses acceptance sampling to evaluate batches of inputs. Ideally, the defect rate would be no more than 3.5 percent. The firm knows that on occasion, batches with that defect rate or higher might be rejected. However, if the defect rate is less than or equal to 3.5 percent, the firm would like there to be very little chance of that batch being rejected. This value, 3.5 percent, is the firm's:

Q: Suppose we have a lot of several thousand units of a finished good. For an acceptance sampling plan with n = 20 and c = 2, what will be the average outgoing quality for lots with 5 percent defectives? 10 percent? 15 percent? 20 percent?

Q: Given the following acceptance sampling data for a lot of several thousand units of a finished good: Per-unit cost of replacing a defective unit after it has been shipped is $5.00 Per-unit cost of 100 percent inspection prior to shipment is $.60. What is the point of indifference between 100 percent inspection and shipment without inspection?

Q: A manufacturer purchases large quantities of metal brackets from several suppliers. The brackets are shipped in lots of 8,000 each. Random samples of 40 brackets are taken from each lot, and the lot is rejected if any defectives are discovered. Rejected lots are subjected to 100 percent inspection, and any defectives are replaced with good brackets. Determine the average outgoing quality limit for this sampling plan.

Q: A firm that makes plastic wrapping material takes random samples of 50 items from each lot before it is sent to a customer. Lots contain 2,000 items each. Any lot with more than one defective is subjected to 100 percent inspection, and any defectives are replaced with good ones. (A) Construct the OC curve for this plan. (B) Construct the AOQ curve for this plan. What is the approximate AOQ limit?

Q: Shipments of bowling balls are sampled before delivery to a warehouse. Lots of 600 balls are checked, using 10 observations from each lot. Any lot with more than one defective is rejected. Calculate values for the operating characteristic curve for this sampling plan.

Q: The quality manager for Microelectronics, Inc., is concerned about the quality of the batch of several thousand Z-box games which his company is about to ship. If, based on his acceptance sample, he decides to ship this batch without inspection, which type error would be possible? A. inspector's error B. producer's error C. Type I error D. Type II error E. both Type I and Type II errors

Q: The quality manager for Microelectronics, Inc., is concerned about the quality of the batch of several thousand Z-box games which his company is about to ship. If he uses an acceptance sampling plan of n = 20 and c = 1, what will be the average outgoing quality for batches with 15 percent defectives? A. .0263 B. .1237 C. .1756 D. .8244 E. .9737

Q: The quality manager for Microelectronics, Inc., is concerned about the quality of the batch of several thousand Z-box games which his company is about to ship. If he uses an acceptance sampling plan of n = 20 and c = 1, what is the probability that, if this batch is 15 percent defectives, it will be rejected and completely inspected prior to shipment? A. .0263 B. .1237 C. .1756 D. .8244 E. .9737

Q: The quality manager for Microelectronics, Inc., is concerned about the quality of the batch of several thousand Z-box games which his company is about to ship. If the cost of replacing a defective Z-box game once it has been shipped is $5.00, while the cost of complete (100 percent) inspection prior to shipment is $.20 each, at what point is he indifferent between complete inspection and shipment without inspection? A. 0 percent defectives B. 4 percent defectives C. 5 percent defectives D. 9 percent defectives E. 22 percent defectives

Q: The quality manager for Frozen Pizzas, Inc., is concerned about the quality of the lot of several thousand pizzas which his company produced this week, and is now ready to ship. If he uses an acceptance sampling plan of n = 8 and c = 1, what will be the average outgoing quality for lots with 10 percent defectives? A. .0813 B. .0962 C. .1869 D. .7318 E. .8131

Q: The quality manager for Frozen Pizzas, Inc., is concerned about the quality of the lot of several thousand pizzas which his company produced this week, and is now ready to ship. If he uses an acceptance sampling plan of n = 8 and c = 1, what is the probability that, if this lot is 15 percent defective, it will be rejected and completely inspected prior to shipment? A. .8948 B. .8131 C. .6572 D. .5033 E. .3428

Q: The quality manager for Frozen Pizzas, Inc., is concerned about the quality of the lot of several thousand pizzas which his company produced this week, and is now ready to ship. If he uses an acceptance sampling plan of n = 8 and c = 1, what is the probability that, if this lot is 10 percent defective, it will be accepted for shipment without inspection? A. .9619 B. .9428 C. .8131 D. .4305 E. .1869

Q: The quality manager for Frozen Pizzas, Inc., is concerned about the quality of the lot of several thousand pizzas which his company produced this week, and is now ready to ship. If the cost of replacing a defective pizza once it has been shipped is $5.00, while the cost of complete (100 percent) inspection prior to shipment is $.30 per pizza, what is the point of indifference between complete inspection and shipment without inspection? A. 1.67 percent defectives B. 3 percent defectives C. 5 percent defectives D. 6 percent defectives E. 16.7 percent defectives

Q: The quality manager for Graphics, Inc., is concerned about the quality of the lot of several thousand posters which her company printed this week and is now preparing to ship. If the indifference point between complete inspection and shipment without inspection is 12 percent defectives, and she decides to sample 15 posters (n = 15), what is the maximum number of sample defectives (c) for which this lot would be accepted for shipment without further inspection? A. 0 defectives B. 1 defective C. 2 defectives D. 3 defectives E. 4 defectives

Q: The quality manager for Graphics, Inc., is concerned about the quality of the lot of several thousand posters which her company printed this week and is now preparing to ship. If, based on her acceptance sample, she decides to ship this lot without inspection, which type error would be possible? A. Type I B. Type II C. both Type I and Type II errors D. neither Type I nor Type II error E. cannot be determined without further data

Q: The quality manager for Graphics, Inc., is concerned about the quality of the lot of several thousand posters which her company printed this week and is now preparing to ship. If she uses an acceptance sampling plan of n = 10 and c = 2, what will be the average outgoing quality for lots with 20 percent defectives? A. .13556 B. .20000 C. .23630 D. .58434 E. .32484

Q: The quality manager for Graphics, Inc., is concerned about the quality of the lot of several thousand posters which her company printed this week and is now preparing to ship. If she uses an acceptance sampling plan of n = 10 and c = 2, what is the probability that, if this lot is 10 percent defective, it will be accepted for shipment without inspection? A. .9298 B. .0702 C. .8189 D. .2198 E. .5995

Q: The quality manager for Graphics, Inc., is concerned about the quality of the lot of several thousand posters which her company printed this week and is now preparing to ship. If the cost of replacing a defective poster once it has been shipped is $10.00, while the cost of complete 100 percent inspection prior to shipment is $.50 per poster, at what point is she indifferent between complete inspection and shipment without inspection? A. 5 percent B. 10 percent C. 12 percent D. 20 percent E. 25 percent

Q: A quality inspector for Alpha-Beta Co. is concerned about the quality of the batch of several thousand blank DVD disks which his company produced this week and is preparing to ship. If, based on his acceptance sample, he decides to ship this batch without inspection, which type error would be possible? A. inspector's error B. producer's error C. Type I error D. Type II error E. both Type I and Type II errors

Q: A quality inspector for Alpha-Beta Co. is concerned about the quality of the batch of several thousand blank DVD disks which his company produced this week and is preparing to ship. If he uses an acceptance sampling plan of n = 5 and c = 2, what will be the average outgoing quality for batches with 40 percent defectives? A. .1270 B. .2730 C. .3174 D. .6826 E. .7270

Q: A quality inspector for Alpha-Beta Co. is concerned about the quality of the batch of several thousand blank DVD disks which his company produced this week and is preparing to ship. If he uses an acceptance sampling plan of n = 5 and c = 2, what is the probability that, if this batch is 40 percent defective, it will be rejected and receive 100 percent inspection prior to shipment? A. .1270 B. .2730 C. .3174 D. .6826 E. .7270

Q: A quality inspector for Alpha-Beta Co. is concerned about the quality of the batch of several thousand blank DVD disks which his company produced this week and is preparing to ship. If the cost of replacing a defective DVD disk once it has been shipped is $2.00, while the cost of 100 percent inspection prior to shipment is $.40 each, at what point is he indifferent between 100 percent inspection and shipment without inspection? A. 0 percent defectives B. 2 percent defectives C. 5 percent defectives D. 20 percent defectives E. 30 percent defectives

Q: In acceptance sampling, the level of inspection automatically adjusts to the quality of lots being inspected, assuming that: A. a single-sampling plan is used. B. double-sampling plans are used. C. multiple-sampling plans are used. D. "rejected" lots are subjected to 100 percent inspection. E. the incoming fraction defective remains constant.

Q: An AOQ curve shows: A. the maximum quality. B. average outgoing quality relative to incoming quality. C. how well a sampling plan can discriminate between good and bad lots. D. the actual quality level. E. "good" quality.

Q: A Type I (alpha) error occurs when: A. a bad lot is accepted. B. a good lot is rejected. C. a bad lot is rejected. D. a good lot is accepted. E. an accepted lot is reinspected.

Q: A Type II (beta) error occurs when: A. a bad lot is accepted. B. a good lot is rejected. C. a bad lot is rejected. D. a good lot is accepted. E. a rejected lot is reinspected.

Q: The AQL indicates: A. acceptable quality level. B. average quality level. C. actual quality level. D. aggregate quality level. E. approximate quality level.

Q: The ability of a sampling plan to discriminate between lots of high quality and lots of low quality is described by: A. a Gantt chart. B. an operating characteristic curve. C. an average outgoing quality curve. D. a process control chart. E. a range chart.

Q: An OC curve shows: A. average outgoing quality. B. the average outgoing quality limit. C. out-of-control criteria. D. operating control. E. probability of acceptance versus lot quality.

Q: A lot can be "accepted" or "rejected" in a multiple-sampling plan: A. after one sample is taken. B. after two samples are taken. C. after three or more samples are taken. D. all of the choices. E. none of the choices.

Q: A lot can be "accepted" or "rejected" in a double-sampling plan: A. after one sample is taken. B. after two samples are taken. C. only after two samples are taken. D. All choices are correct. E. Only after one and after two samples are taken is correct.

Q: Sampling plans typically specify: A. lot size. B. sample size. C. number of samples to be taken. D. acceptance/rejection criteria. E. all choices are correct.

Q: Which one of the following would not be a reason for using acceptance sampling? A. high cost of passing defectives B. large number of items C. destructive testing D. boredom and fatigue that would accompany complete inspection E. low cost of passing defectives

Q: Acceptance sampling plans might call for the selection of: A. one or more samples. B. a variable number of samples based on actual results. C. random inspections. D. outside audits by testing agencies. E. 100 percent inspection.

Q: The purpose of acceptance sampling is to: A. estimate process quality. B. estimate lot quality. C. detect and eliminate defectives. D. decide if a lot meets predetermined standards. E. accept samples of products.

Q: Suppose that only two incoming fraction defective levels, 2 percent and 6 percent, are possible. The 2 percent incoming fraction defective level is twice as likely as the 6 percent. At a 2 percent incoming fraction defective, there's an 80 percent chance that a lot will be accepted. At 6 percent incoming fraction defective, there's a 20 percent chance that a lot will be accepted. Lots that are not accepted are subject to 100 percent sorting. What is average outgoing quality (approximately)? A. 1.60 percent B. 1.47 percent C. 1.20 percent D. .73 percent E. .80 percent

Q: Suppose that only two incoming fraction defective levels, 4 percent and 8 percent, are possible. These incoming fraction defective levels are equally likely. At a 4 percent incoming fraction defective, there's a 60 percent chance that a lot will be accepted. At 8 percent incoming fraction defective, there's a 20 percent chance that a lot will be accepted. Lots that are not accepted are subject to 100 percent sorting. What is average outgoing quality? A. 40 percent B. 20 percent C. 10 percent D. 4 percent E. 2 percent

Q: When is the average outgoing quality level (AOQL) at its peak? A. when the incoming fraction defective is at a minimum B. when the incoming fraction defective is at a maximum C. when the outgoing fraction defective is at a minimum D. when the outgoing fraction defective is constant E. when the outgoing fraction defective begins to increase

Q: Which of the following is associated with producer's risk? A. LTPD B. AQL C. AOQL D. SPC E. Cpk

Q: Which of the following is associated with consumer's risk? A. LTPD B. AQL C. AOQL D. SPC E. Cpk

Q: A graphical representation that shows the risk of: (1) accepting bad lots and (2) rejecting good lots is called the: A. indifference curve. B. operating characteristic curve. C. sampling plan. D. inspection curve. E. operating inspection plan.

Q: The ability of an acceptance sampling plan to discriminate between good and bad lots is described by its operating characteristic curve.

Q: In a double-sampling plan, a second sample is taken if the results of the first sample are inconclusive.

Q: Acceptance sampling is a form of inspection applied to items during an ongoing process.

Q: In a double-sampling plan, a second sample may not be taken if the results of the first sample are conclusive.

Q: Sampling plans are designed considering both the cost and time required for the inspection.

Q: A double-sampling plan requires a second sample of exactly twice the size of the first sample.

Q: In a single-sampling plan, the entire lot, or batch of items, is accepted or rejected based upon only one specified sized sample.

Q: Acceptance sampling plans must specify the lot size, the sample size, and the acceptance/rejection criteria.

Q: Acceptance sampling procedures can be applied to both attribute and variables inspection.

Q: Acceptance sampling is most useful when the cost consequences of passing defectives are low.

Q: A good sampling plan will occasionally reject a lot with very good quality.

Q: The purpose of acceptance sampling is to decide whether a batch of items satisfies pre-determined standards.

Q: Flexible acceptance sampling revises the sampling plan in response to actual results.

Q: Acceptance sampling procedures are applicable for inspection both before and after production.

Q: Acceptance sampling is applied to batches of items during the production process.

Q: A campaign manager for a political candidate must arrange the shipment of 150 cartons of campaign buttons from three button producers to three campaign headquarters. The supplies and demands, and the per-carton transportation costs, are shown below: Which of the following is a constraint for the customer (campaign headquarters)? A. B. C. D. E.all of the choices

Q: In a transportation problem with three locations and two destinations, the objective function is as follows: Min 20X11 + 18X21 + 23X31 + 16X12 + 14X22 + 12X32. How much does it cost to ship one unit from location 2 to destination 1? A. 18 B. 12 C. 23 D. 16 E. none of the choices

Q: A transportation planner has set up the following spreadsheet formulation of a transportation problem: Suppose the output from this formulation is as follows: How many units are shipped from location II to location C? A. 0 B. 60 C. 70 D. 80 E. none of these

Q: 18. In a transportation problem with three locations and two destinations, the objective function is as follows: Min 20X11 + 18X21 + 23X31 + 16X12 + 14X22 + 12X32. How much does it cost to ship one unit from location 1 to destination 2? A. 18 B. 12 C. 23 D. 16 E. 14