Exam 17: Statistical Applications in Quality Management

TABLE 17-6 The maker of a packaged candy wants to evaluate the quality of her production process.On each of 16 consecutive days,she samples 600 bags of candy and determines the number in each day's sample that she considers to be of poor quality.The data that she developed follow. -Referring to Table 17-6,construct a p control chart for these data.

TABLE 17-3 A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day. -Referring to Table 17-3,suppose the analyst constructs an R chart to see if the variability in production times is in-control.What is the center line of this R chart?

Which of the following situations suggests a process that appears to be operating in a state of statistical control?

TABLE 17-5 A manufacturer of computer disks took samples of 240 disks on 15 consecutive days.The number of disks with bad sectors was determined for each of these samples.The results are in the table that follows. -Referring to Table 17-5,a p control chart is to be made for these data.The center line of the control chart is ________.

TABLE 17-7 A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process.She takes samples of size 5 from each day's output and counts the number of blemishes on each silicone sheet.The results from 20 days of such evaluations are presented below. -Referring to Table 17-7,an R chart is to be constructed for the number of blemishes.The upper control limit for this data set is ________.

Which famous statistician developed the 14 points of quality?

TABLE 17-9 The manufacturer of canned food constructed control charts and analyzed several quality characteristics.One characteristic of interest is the weight of the filled cans.The lower specification limit for weight is 2.95 pounds.The table below provides the range and mean of the weights of five cans tested every fifteen minutes during a day's production. -Referring to Table 17-9,construct an chart for the weight.

A process is said to be out of control if

TABLE 17-5 A manufacturer of computer disks took samples of 240 disks on 15 consecutive days.The number of disks with bad sectors was determined for each of these samples.The results are in the table that follows. -Referring to Table 17-5,construct a p control chart for these data.

TABLE 17-4 A factory supervisor is concerned that the time it takes workers to complete an important production task (measured in seconds)is too erratic and adversely affects expected profits.The supervisor proceeds by randomly sampling 5 individuals per hour for a period of 10 hours.The sample mean and range for each hour are listed below. She also decides that lower and upper specification limit for the critical-to-quality variable should be 10 and 30 seconds, respectively. -Referring to Table 17-4,suppose the sample mean and range data were based on 6 observations per hour instead of 5.How would this change affect the lower and upper control limits of an R chart?

TABLE 17-8 Recently,a university switched to a new type of computer-based registration.The registrar is concerned with the amount of time students are spending on the computer registering under the new system.She decides to randomly select 8 students on each of the 12 days of the registration and determine the time each spends on the computer registering.The range,mean,and standard deviation of the times required to register are in the table that follows. -Referring to Table 17-8,an chart is to be used for the time required to register.The lower control limit for this data set is ________,while the upper control limit is ________.

TABLE 17-3 A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day. -Referring to Table 17-3,suppose the analyst constructs an chart to see if the production process is in-control.What is the center line for this chart?

TABLE 17-6 The maker of a packaged candy wants to evaluate the quality of her production process.On each of 16 consecutive days,she samples 600 bags of candy and determines the number in each day's sample that she considers to be of poor quality.The data that she developed follow. -Referring to Table 17-6,the estimate of the proportion of poor quality bags of candy is ________.

Once the control limits are set for a control chart,one attempts to

TABLE 17-7 A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process.She takes samples of size 5 from each day's output and counts the number of blemishes on each silicone sheet.The results from 20 days of such evaluations are presented below. -Referring to Table 17-7,based on the chart for the number of blemishes,it appears that the process is out of control.

The C_pk is a one-sided specification limit.

TABLE 17-3 A quality control analyst for a light bulb manufacturer is concerned that the time it takes to produce a batch of light bulbs is too erratic.Accordingly,the analyst randomly surveys 10 production periods each day for 14 days and records the sample mean and range for each day. -Referring to Table 17-3,suppose the analyst constructs an chart to see if the production process is in-control.Which expression best describes this chart?

TABLE 17-9 The manufacturer of canned food constructed control charts and analyzed several quality characteristics.One characteristic of interest is the weight of the filled cans.The lower specification limit for weight is 2.95 pounds.The table below provides the range and mean of the weights of five cans tested every fifteen minutes during a day's production. -Referring to Table 17-9,based on the chart,it appears that the process is in control.

TABLE 17-10 Below is the number of defective items from a production line over twenty consecutive morning shifts. -Referring to Table 17-10,a c chart is to be constructed for the number of defective items.The lower control limits is ________.

Which of the following is not part of the Shewhart-Deming cycle?