Exam 12: Statistically Based Quality Improvement for Attributes

A manufacturer of FAX machines checks samples of 50 units for functionality at the conclusion of the assembly process. The results of 10 samples are shown below: What sample is out of control?

A local fraternity is deciding between three different refrigerators. The refrigerators have a mean time between failure and mean time to repair as shown in the table. What refrigerator(s)will provide the greatest availability?

One item with a reliability of .95, followed by two items in parallel having a reliability of 0.90, have an overall system reliability of 0.94.

A p chart can be used whether or not there is a constant sample size.

________ attributes relate to whether or not a particular product or service performs as it is supposed to.

A producer of contact lenses regularly takes samples of 100 lenses and inspects them for scratches. If a lens has a single scratch, it cannot be sold. The results of 10 samples are shown. What is the average proportion defective?

A quality engineer notes that a process produces data that are binomial and has been obtained using a sample space that is not constant. The primary interest of the process manager is in the percentage of bad parts. An appropriate control chart to use would be a(n)________.

The producers of the Yugo automobile periodically inspect samples of 80 hoods for dents and scratches. A single flaw in a hood renders it unsuitable for installation in one of their fine automobiles. The results of the last 10 samples are shown.. What is the center line for the np chart?

A unit that, as a whole, is not acceptable or does not meet performance requirements is a(n)________.

An irregularity or problem with a larger unit is a(n)________.

What is the reliability of a product with a failure rate of 0.001 per operating hour and a useful life of 1500 hours?

The producers of the Yugo automobile periodically inspect samples of 80 hoods for dents and scratches. A single flaw in a hood renders it unsuitable for installation in one of their fine automobiles. The results of the last 10 samples are shown. What sample is out of control?

________ attributes relate to time.

The object of using process charts is to continually improve your processes.

A local university is deciding between three different computer networks. The network servers have a mean time between failure and mean time to repair as shown in the table. Which server(s)will provide the greatest availability?

Fifty crash helmets are tested for one hundred hours per helmet. Of all the helmets tested, only one experiences a malfunction during the test. What is the failure rate for the helmets?

Three items of reliability 0.90 in series has an overall system reliability of 0.73.

Two components of reliability 0.95 are in parallel and this subsystem is connected in series to a component with a reliability of 0.90. The overall system reliability is ________.

State the five types of attributes.

What are the steps required to develop an attribute control chart?