Q&A Hero

Q: A(n) _______ chart monitors the number of nonconforming units in a subgroup. A. B. R C. C D. p

Q: When employing measurement data to study a process, the __________ monitors the process variation. A. chart B. R chart C. p chart D. natural tolerance E. pattern analysis

Q: Common causes of variation represent the inherent variability of a given process.

Q: If a company is using an chart for a given process with measurement data, it is generally not important or necessary to use an R chart or s chart.

Q: Reducing common causes of variation usually requires action by management.

Q: If a process is stable and in statistical control, it is not influenced by assignable causes of variation.

Q: Control charts are used to reduce common causes of variation.

Q: If a process is only influenced by common causes of variation, we can state that the process is in statistical control.

Q: If a manufacturing process is in statistical control, it means that the process is capable of producing products that meet the needs of the customers.

Q: A sequence of steadily decreasing points on a control chart is called run down.

Q: How well the design of the product meets and exceeds the needs and expectations of the customers is called the quality of performance.

Q: How well a process is able to meet the requirements set forth by the process design is called the quality of design.

Q: A cause-and-effect diagram enumerates the potential causes of an undesirable effect on the process to discover sources of process variation and to identify opportunities for process improvement.

Q: When using and R charts to analyze and improve a process, first, the chart is analyzed and the necessary action(s) to correct assignable causes of variation is (are) taken before the R chart is analyzed.

Q: Unusual sources of variation that can be attributed to specific causes are called the common causes of process variation.

Q: For a given control chart, zone boundaries consist of the UCL and LCL.

Q: A goal of statistical process control is continuous process improvement.

Q: Sigma level capability is the number of estimated process standard deviations between the estimated process mean and the specification limit closest to the estimated process mean.

Q: Periodic sampling is observing the output of a process at random intervals.

Q: Process leeway is the distance between natural tolerance limits and control limits.

Q: A p chart is a control chart on which the proportions of nonconforming units are plotted versus time.

Q: A range chart is a control chart on which ranges between individual process measurements within a subgroup are plotted.

Q: An chart is a control chart on which individual process measurements are plotted versus time.

Q: A control chart is a graph whose purpose is to detect assignable causes of variation in a process.

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range of 8.85. Find the sigma level capability of the process.A. 4.64B. −4.66C. 7.83D. 2.25

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range of 8.85. Is the process capable of meeting the specifications?A. YesB. No

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range of 8.85. Assuming that the process is in statistical control, calculate the natural tolerance limits for the process. A. [45.75, 54.35] B. [37.16, 62.94] C. [42.40, 57.70] D. [47.50, 52.60]

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, in order to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range of 8.85. Calculate the control limits for the R chart. A. [3.07, 14.63] B. [6.57, 11.13] C. [0, 35.40] D. [0, 20.20]

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, in order to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range = 8.85. Calculate the control limits for the X-bar chart. A. [41.2, 58.9] B. [48.1, 52.0] C. [43.6, 56.5] D. [29.9, 70.2]

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, in order to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range = 8.85. Calculate the center line for the R chart. A. 50.05 B. 8.85 C. 2.21 D. 0.59

Q: A manufacturer of windows produces one type that has a plastic coating. The specification limits for the plastic coating are 30 and 70. From time to time the plastic coating can become uneven. Therefore, in order to keep the coating as even as possible, thickness measurements are periodically taken at four different locations on the window. 15 subgroups were observed, each consisting of four thickness measurements, with the following results: mean of the means = = 50.05, and average range = 8.85. Calculate the center line for the X-bar chart. A. 50.05 B. 8.85 C. 4.12 D. 3.34

Q: A bank officer wishes to study how many customers write bad checks. To accomplish this, the officer randomly selects a weekly sample of 100 checking accounts and records the number that wrote bad checks. The numbers of customers who wrote bad checks in 20 consecutive weekly samples of 100 account holders are, respectively, 1, 4, 9, 0, 4, 6, 0, 3, 8, 5, 3, 5, 2, 9, 4, 4, 3, 6, 4, and 0. On the basis of the limits established, if the bank finds that 12 customers in the next weekly sample of 100 account holders have written bad checks, should the bank believe that there has been an unusual variation in the process?A. YesB. No

Q: A bank officer wishes to study how many customers write bad checks. To accomplish this, the officer randomly selects a weekly sample of 100 checking accounts and records the number that wrote bad checks. The numbers of customers who wrote bad checks in 20 consecutive weekly samples of 100 account holders are, respectively, 1, 4, 9, 0, 4, 6, 0, 3, 8, 5, 3, 5, 2, 9, 4, 4, 3, 6, 4, and 0. Find the LCL and UCL for the p chart. A. [.0204, .0596] B. [.034, .046] C. [0, .0988] D. [0, .171]

Q: A bank officer wishes to study how many customers write bad checks. To accomplish this, the officer randomly selects a weekly sample of 100 checking accounts and records the number that wrote bad checks. The numbers of customers who wrote bad checks in 20 consecutive weekly samples of 100 account holders are, respectively, 1, 4, 9, 0, 4, 6, 0, 3, 8, 5, 3, 5, 2, 9, 4, 4, 3, 6, 4, and 0. Find the appropriate center line. A. .08 B. .01 C. .09 D. .04

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. To keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. How many standard deviations of leeway exist between x and the specification closest to x? A. 1.76 B. 1.51 C. 2.55 D. 0.45

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. In order to keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Find the sigma level capability of the process. A. 3.45 B. 0.45 C. 1.24 D. 1.49

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. To keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Is the process capable of meeting the specifications?A. YesB. No

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. In order to keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Assuming that the process is in statistical control, calculate the natural tolerance limits for the process. A. [1.47, 7.53] B. [3.197, 5.803] C. [3.729, 5.271] D. [4.066, 4.934]

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. To keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Calculate the control limits for the R chart. A. [.464, 1.556] B. [0, 2.349] C. [0, 2.114] D. [0, 2.135]

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. In order to keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Calculate the control limits for the X-bar chart. A. [4.345, 4.655] B. [3.49, 5.51] C. [3.917, 5.083] D. [2.365, 6.635]

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. In order to keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Calculate the center line for the R chart. A. 1.01 B. 0.22 C. 4.50 D. 0.90

Q: A motorcycle manufacturer produces the parts for its vehicles in different locations and transports them to its plant for assembly. To keep the assembly operations running efficiently, it is vital that all parts be within specification limits. One important part used in the assembly is the engine camshaft, and one important quality characteristic is the case hardness depth. Specifications state that the hardness depth must be between 3.0 mm and 6.0 mm. To investigate the process, the quality control engineer selected 25 daily subgroups of n = 5 and measured the hardness depth. The process yielded a mean of the means = 4.50 and an average range = 1.01. Calculate the center line for the X-bar chart. A. 1.01 B. 4.50 C. 3.49 D. 0.90

Q: Suppose that and R charts based on subgroups of size 4 are being used to monitor the tire diameter of a new radial tire. The and R charts are found to be in statistical control, with = 50.5, = 1.25 inches. A histogram of the tire diameter measurements indicates that these measurements are approximately normally distributed. Compute the natural tolerance limits for this process. A. [48.68, 52.32] B. [49.89, 51.11] C. [48.86, 52.14] D. [46.75, 54.25]

Q: The quality of an electronic component used in manufacturing cell phones is monitored with a p chart. In the last 20 days, daily samples of 75 units resulted in the following number of defective units per sample: 8, 4, 3, 7, 3, 1, 0, 7, 4, 2, 0, 1, 6, 2, 4, 3, 1, 2, 8, and 5. If on the 21st day, 9 defective units were found in the sample of 75 units, would the process be in control?A. YesB. No

Q: The quality of an electronic component used in manufacturing cell phones is monitored with a p chart. In the last 20 days, daily samples of 75 units resulted in the following number of defective units per sample: 8, 4, 3, 7, 3, 1, 0, 7, 4, 2, 0, 1, 6, 2, 4, 3, 1, 2, 8, and 5. Find the LCL and UCL for the p chart. A. [0, .1208] B. [.0228, .0718] C. [0, .1897] D. [.0445, .0501]

Q: The quality of an electronic component used in manufacturing cell phones is monitored with a p chart. In the last 20 days, daily samples of 75 units resulted in the following number of defective units per sample: 8, 4, 3, 7, 3, 1, 0, 7, 4, 2, 0, 1, 6, 2, 4, 3, 1, 2, 8, and 5. Find the appropriate center line. A. .0473 B. .2667 C. .1067 D. .0133

Q: Among other quality measures, the quality of an electronic component used in manufacturing stereo speakers is monitored with a control chart. In the last 25 days, daily samples of 60 units resulted in the following number of defective units per sample: 8, 4, 3, 7, 6, 2, 5, 3, 1, 0, 7, 4, 2, 0, 1, 6, 2, 4, 3, 1, 2, 8, 5, 6, and 0. Determine the appropriate upper and lower control limits for this process. A. [.029, .091] B. [.056, .064] C. [0, .152] D. [0, .202]

Q: Among other quality measures, the quality of an electronic component used in manufacturing stereo speakers is monitored with a p chart. In the last 25 days, daily samples of 60 units resulted in the following number of defective units per sample: 8, 4, 3, 7, 6, 2, 5, 3, 1, 0, 7, 4, 2, 0, 1, 6, 2, 4, 3, 1, 2, 8, 5, 6, 0. Determine the center line for this process. A. .06 B. .03 C. .001 D. .056

Q: Suppose that a tire manufacturer uses and R charts based on subgroups of size 4 to monitor tire diameter. The and R charts are found to be in statistical control, with = 50.25, = 8. inches. A histogram of the tire diameter measurements indicates that these measurements are approximately normally distributed. Find the sigma level capability of the process. A. 1.93 B. 3.22 C. 0.64 D. 0.22

Q: Suppose that and R charts based on subgroups of size 4 are being used to monitor the tire diameter of a new radial tire. The and R charts are found to be in statistical control with = 50.25, = 8. inches. A histogram of the tire diameter measurements indicates that these measurements are approximately normally distributed. Calculate the estimate of the percentage of tires that are out of specification. A. 1.93% B. 2.68% C. 1.62% D. 17.36%

Q: Suppose that and R charts based on subgroups of size 4 are being used to monitor the tire diameter of a new radial tire. The and R charts are found to be in statistical control with = 50.25, = 8. inches. A histogram of the tire diameter measurements indicates that these measurements are approximately normally distributed. If the tire diameter specifications are 50 inches 1 inch, is the process capable of meeting the specifications?A. YesB. No

Q: A fastener company produces a certain type of bolt for the automobile industry with a nominal (target) length of 2.00 inches. The specifications for the length of the bolt are 2.00 .006 inches. An automobile manufacturer will only purchase from this company if the sigma level of capability of the process is at least 4. If the process mean is equal to 2.001, determine the maximum process standard deviation necessary for the fastener manufacturing company in order to qualify as a supplier for the automobile manufacturing company. A. .0125 B. .005 C. .00125 D. .00025

Q: A fastener company produces bolts with a nominal (target) length of 2.00 inches. The specifications are 2.00 .006 inches. If the process mean is 2.001 and the process standard deviation is .0016, determine the estimated standard deviations of the leeway for this process. A. .0016 B. .0048 C. 1.375 D. .125

Q: A fastener company produces bolts with a nominal (target) length of 2.00 inches. The specifications are 2.00 .006 inches. Determine the upper specification limit and the lower specification limit for this process. A. [1.982, 2.018] B. [1.94, 2.06] C. [1.994, 2.006] D. [1.99, 2.01]

Q: A foreman wants to use an chart to control the average length of the bolts manufactured. He has recently collected the six samples given below. Sample 1 1.99 2.01 2.02 2.02 2 2.00 2.00 2.01 2.01 3 1.98 1.99 2.01 1.98 4 2.01 2.02 2.02 1.99 5 1.99 1.99 2.01 1.99 6 2.03 1.98 2.03 2.04 Determine the LCL and the UCL for the R chart. A. [0, .0685] B. [0, .076] C. [0, .03] D. [0, .0601]

Q: A foreman wants to use an chart to control the average length of the bolts manufactured. He has recently collected the six samples given below. Sample 1 1.99 2.01 2.02 2.02 2 2.00 2.00 2.01 2.01 3 1.98 1.99 2.01 1.98 4 2.01 2.02 2.02 1.99 5 1.99 1.99 2.01 1.99 6 2.03 1.98 2.03 2.04 Determine the LCL and the UCL for the chart. A. [1.975, 2.035] B. [1.915, 2.095] C. [1.983, 2.027] D. [1.991, 2.019]

Q: A foreman wants to use an chart to control the average length of the bolts manufactured. He has recently collected the six samples given below. Sample 1 1.99 2.01 2.02 2.02 2 2.00 2.00 2.01 2.01 3 1.98 1.99 2.01 1.98 4 2.01 2.02 2.02 1.99 5 1.99 1.99 2.01 1.99 6 2.03 1.98 2.03 2.04 Calculate the average range. A. .036 B. .18 C. .030 D. .05

Q: A foreman wants to use an chart to control the average length of the bolts manufactured. He has recently collected the six samples given below.Sample1 1.99 2.01 2.02 2.022 2.00 2.00 2.01 2.013 1.98 1.99 2.01 1.984 2.01 2.02 2.02 1.995 1.99 1.99 2.01 1.996 2.03 1.98 2.03 2.04Calculate the mean of the means().A. 2.010B. 2.406C. 2.000D. 2.005

Q: Use this information about 10 shipments of lightbulbs. Shipment 1 2 3 4 5 6 7 8 9 10 # of defective units 0 1 2 0 4 3 2 1 3 4 If 200 lightbulbs are selected at random from each of 10 shipments and the number of defectives in each shipment is given above, find the LCL and the UCL for the p chart. A. [0, .1044] B. [.003, .017] C. [0, .0311] D. [.009, .0115]

Q: Use this information about 10 shipments of lightbulbs. Shipment 1 2 3 4 5 6 7 8 9 10 # of defective units 0 1 2 0 4 3 2 1 3 4 If 400 bulbs are selected at random from each of 10 shipments and the number of defectives in each shipment is given above, find the appropriate center line. A. .005 B. .05 C. .0025 D. .01

Q: Assume that 25 samples of 50 each are taken and the total number of defectives is 34. Find the LCL and UCL for the p chart.A. [.0134, .0410]B. [0, .0962]C. [.0042, .0502]D. [.0239, .0304]

Q: Assume that 25 samples of 50 each are taken and the total number of defectives is 34. Calculate . A. .680 B. .453 C. .816 D. .0272

Q: In 20 samples, there are 80 units defective. If each sample consists of 100 units, find the appropriate UCL and the LCL for the p chart. A. [.0269, .0531] B. [.0204, .0596] C. [.0380, .0420] D. [0, .0988]

Q: From 20 samples of size 100, a total of 80 units are defective. What is the centerline for the p chart? A. .04 B. .4 C. .8 D. .08

Q: If 20 samples of size 7 are drawn, with = 33.33 and = 5.65, what are the LCL and UCL for the R chart? A. [2.345, 8.955] B. [.076, 1.924] C. [.415, 1.585] D. [.429, 10.871]

Q: If 20 samples of size 7 are drawn, with = 33.33 and = 5.65, what is the A-B upper boundary for the chart? A. 35.697 B. 34.908 C. 34.347 D. 34.008

Q: If 20 samples of size 7 are drawn, with = 33.33 and = 5.65, what are the LCL and the UCL for the chart? A. [32.313, 34.347] B. [30.963, 35.697] C. [27.68, 38.98] D. [32.911, 33.749]

Q: If = .0139 and 25 shipments of 20 items each were examined, what are the UCL and the LCL for the p chart? A. [.0118, .0159] B. [0, .0401] C. [.008, .0198] D. [0, .0924]

Q: If = 2.0144, = .0972, and there are 25 subgroups of size 5, find the UCL and the LCL for the R chart. A. [.045, .1498] B. [.0972, .2055] C. [0, .2055] D. [0.2, 114]

Q: If = 2.0144, = .0972, and there are 25 subgroups of size 5, find the UCL and the LCL for the chart. A. [1.999, 2.029] B. [1.958, 2.071] C. [1.917, 2.112] D. [1.437, 2.591]

Q: If = 16.1, = .03, and n = 6, and if the specifications are [15.9, 16.3], is the process capable?A. YesB. No

Q: If = 16.1, = .03, and n = 6, calculate the natural tolerance limits. A. [16.065, 16.135] B. [16.088, 16.112] C. [15.745, 16.455] D. [16.055, 16.145]

Q: If = 5.2, = .3, and n = 4, and if the specifications are [4.6, 5.8], is the process capable?A. YesB. No

Q: If = 5.2, = .3, and n = 4, calculate the natural tolerance limits. A. [5.054, 5.346] B. [4.3, 6.1] C. [4.806, 5.594] D. [4.763, 5.637]

Q: _________ is the set of international standards on quality management and quality assurance systems. It establishes processes for assuring that goods and services offered by the company meet a consistent level of quality acceptable to customers. A. Control Charting B. SQC C. ISO 9000 D. ASQC

Q: A unit that fails to meet specifications is called a _____________ unit. A. conforming B. capable C. defective D. common cause

Q: If and R charts are used to control a manufacturing process, an ______ chart is analyzed first and brought into a state of statistical control before preparing the _______ chart.A. R, B. , R

Q: How well a process is able to meet the requirements set forth by the process design is called the quality of _____________. A. performance B. conformance C. design D. control

Q: How well a product or a service performs in the marketplace is called the quality of ______________. A. performance B. conformance C. design D. control

Q: The number of estimated process standard deviations between and the closest specification limit is the _____________ of the process. A. sigma level capability B. leeway C. mean D. capability