Exam 4: Statistical Process Control

Easy Tax is a service company that prepares tax returns.An outside auditor has examined 20 samples each containing one completed tax return.The total number of defects observed over the 20 samples is 200.The UCL for the control chart constructed using three sigma is

Consider a production process that produces batteries.A quality engineer has taken 20 samples each containing 100 batteries.The total number of defective batteries observed over the 20 samples is 200.The sample standard deviation is

Two types of variation associated with the output of a process are common cause (random)and special cause (nonrandom).

Attribute control charts are used to monitor descriptive characteristics of the output of a process rather than measurable characteristics.

Which of the following could be responsible for variability that is special cause (nonrandom)?

Which of the following control charts are often based on sample sizes equal to or larger than one hundred?

Consider a production process that produces batteries.A quality engineer has taken 20 samples each containing 100 batteries.The total number of defective batteries observed over the 20 samples is 200.The UCL for the control chart constructed using two sigma is

Which of the following services can be measured and monitored with control charts?

XYZ manufacturing has received an order to produce a rod 5 inches in diameter + .04 inch.In sample runs,the machine tool that will be making the rod has been able to produce rods with a mean diameter of 4.99 inches and a standard deviation of 0.011 inch.The process capability index for this process is

Consider a production process that produces tires.A quality engineer has taken 15 samples,each containing 200 tires.The total number of defective tires over the 15 samples is 340.The UCL for the control chart constructed using two sigma is

Which of the following control charts is used to monitor the percent of defective items within a sample?

Control limits are based on the special cause (nonrandom)variation inherent in a process.

Tolerances or specification limits are allowable variation prescribed in a product design.

The range measures the variation within samples versus the variation between samples.

A company produces a product which is designed to weigh 10 oz. ,with a tolerance of + 0.5 oz.The process produces products with an average weight of 9.95 oz.and a standard deviation of 0.10 oz.According to the process capability index

A control chart that uses the actual number of defects per item to monitor a process is known as a

If the quality of a process's output is determined by classifying the output as being defective or not defective,use a(n)________control chart.

When constructing a control chart for the first time,all points should be within the control limits indicating the process is in control.

Consider a production process that produces tires.A quality engineer has taken 15 samples,each containing 200 tires.The total number of defective tires over the 15 samples is 340.The sample standard deviation is

The formula used to determine the upper and lower control limits are based on product specification limits.