Exam 19: Statistical Process Control and Quality Management

A new printing machine is set or calibrated to print 25 copies per minute. On each of four days, the printer's output is measured five times. The data will be used to construct a process control chart to monitor the printing process. The results of the printing process are in the following table. What is the mean for Day 1?

A fishbone diagram classifies potential causes into categories. What are they?

Random samples of 4 items are selected from a manufacturing process at regular intervals and a certain quality characteristic is measured. After 25 samples, $\Sigma$ X = 15,350 and $\Sigma$ R = 411.4 To construct a mean chart, what is the value for R bar used to compute the limits?

Mean charts are designed to determine whether a process is in or out of control based on sample means.

A new machine used in the production of motor mount bolts was put into operation. Five samples of size 100 were randomly selected and the number of defectives in each sample was noted. What is the upper control limit (UCL)?

A manufacturer of cell phones counts the number of defective phones in an eight hour shift. Over the last ten days, the number of defective shafts per eight hour shift has been reported. What is the average number of defects per eight hour shift?

In acceptance sampling, there is one unique operating characteristic curve for a specified sampling plan.

Cappelli Inc. designs and manufactures women's apparel using material from various mills. Their acceptance sampling plan states that 20 two inch squares of the incoming material must be carefully checked. If 3 or less squares reveal imperfections, the lot is accepted. What is the probability that an incoming lot from Blufton Mills that contains 40 percent imperfect cloth will be accepted?

A manufacturer of golf club shafts inspects fifty shafts every day. Over the last ten days, the number of defective shafts has been reported. What is the mean proportion of defective shafts?

A quality control chart is used to monitor the customer wait time at a local call center. Sample means of five times are averaged and plotted over time. The last five sample means show a trend of increasing sample means. The process is

What variation is due to slight changes in materials or process conditions and is random in nature? ________________

A new machine is set or calibrated to fill tubes of toothpaste at precisely 6.75 ounces. Then, once the machine is running, a sample of 6 tubes is taken every three hours and weighed with the following results: What is the range of the samples at 4 pm?

Random samples of 4 items are selected from a manufacturing process at regular intervals and a certain quality characteristic is measured. After 25 samples, $\Sigma$ X = 15,350 and $\Sigma$ R = 411.4 To construct a range chart, what is the lower control limit (LCL) for the range?

A fishbone diagram is used to determine if a process is out of control.

A new printing machine is set or calibrated to print 25 copies per minute. On each of four days, the printer's output is measured five times. The data will be used to construct a process control chart to monitor the printing process. The results of the printing process are in the following table. What is the lower control limit (LCL) for the mean chart?

Random samples of 4 items are selected from a manufacturing process at regular intervals and a certain quality characteristic is measured. After 25 samples, $\Sigma$ X = 15,350 and $\Sigma$ R = 411.4 To construct a mean chart what is the value for the center line?

Random samples of 4 items are selected from a manufacturing process at regular intervals and a certain quality characteristic is measured. After 25 samples, $\Sigma$ X = 15,350 and $\Sigma$ R = 411.4 To construct a mean chart, what is the upper control limit (UCL) for the mean?

Random samples of 4 items are selected from a manufacturing process at regular intervals and a certain quality characteristic is measured. After 25 samples, $\Sigma$ X = 15,350 and $\Sigma$ R = 411.4 To construct a mean chart, what is the lower control limit (LCL) for the mean?

The cause-and-effect chart is an example of a

A manufacturer of golf club shafts inspects fifty shafts every day. Over the last ten days, the number of defective shafts has been reported. What is the standard error of the mean proportion of defective shafts?