Question 1

The natural tolerance limits for a normally distributed process that is in statistical control:

Accepted Answer

The natural tolerance limits for a normally distributed process that is in statistical control contain approximately 99.73 percent of the individual process measurements, according to the three-sigma rule. When a process is capable, the tolerances are within the specification limits. Therefore, both options B and C are correct. Option A is not true since the specification limits are the boundaries provided by the customer, and if the natural tolerance limits are beyond the specification limits, then the process is not considered capable.

Question 2

When employing measurement data to study a process,the ______ monitors the process mean.

Accepted Answer

The answer of When employing measurement data to study a...

Question 3

Consider two processes.Process 1's mean is equal to its target (nominal)value,while the process 2's mean is not equal to its target value.The Cpkvalue for process 1 will _____,Cpkvalue for process 2.

Accepted Answer

Cpk is a measure of process capability, which is calculated by taking the minimum of the difference between the process mean and the specification limits, divided by three times the process standard deviation. Since process 1's mean is equal to its target (nominal) value, the difference between the mean and the specification limits is zero, resulting in a higher Cpk value. On the other hand, process 2's mean is not equal to its target value, which means that the difference between the mean and the specification limits is greater and the Cpk value will be smaller than process 1's Cpk value. Therefore, the Cpk value for process 1 will always be larger than process 2's Cpk value.

Question 4

In a manufacturing process,if the limits for a control chart are set too _____________,the risk of not investigating a special cause of variation and possibly not taking a corrective action ____________.

Accepted Answer

If the limits are set too loose, it increases the risk of not detecting a special cause of variation, leading to a lack of corrective action.

Question 5

As the standard deviation of a process ___________,the process capability measured by Cpk________.

Accepted Answer

As the standard deviation decreases, the process variability reduces, leading to an increase in process capability, hence increasing Cpk.

Question 6

Rational subgrouping allows us to detect changes _____ subgroups.

Accepted Answer

The answer of Rational subgrouping allows us to detect changes...

Question 7

In a manufacturing process,if the limits for a control chart are set too _____________,the risk of unnecessarily tampering with the process ____________.

Accepted Answer

If the limits for a control chart are set too tight, it means that the control limits are very close to the process mean, which increases the risk of falsely identifying common cause variations as special cause variations. This may lead to unnecessary tampering with the process, which could actually increase the variation and negatively impact the process performance. Hence, it is best to set the control limits at a reasonable distance from the process mean to detect the real changes in the process performance and avoid unnecessary intervention. Setting the control limits too loose may also increase the risk of missing real changes in the process, but it may not necessarily lead to tampering with the process.

Question 8

Common causes of process variation:

Accepted Answer

The answer of Common causes of process variation:
...

Question 9

Observing the output of a process at fixed time intervals is referred to as _____ sampling.

Accepted Answer

Periodic sampling is when output is observed at fixed time intervals. The other options do not indicate fixed intervals.

Question 10

How well a product or service performs in the marketplace is called:

Accepted Answer

Quality of performance refers to how well a product or service meets the needs and expectations of the marketplace, therefore it is the most appropriate choice for the given context. Process capability, quality of conformance, quality of design, and process control are all important aspects of quality management, but do not directly relate to how well a product or service performs in the marketplace.

Question 11

When employing measurement data to study a process,the _______ monitors the process variation.

Accepted Answer

The answer of When employing measurement data to study a...

Question 12

How well a process is able to meet the requirements set forth by the process design is called

Accepted Answer

Quality of conformance refers to how well a process is able to meet the requirements set forth by the process design. Quality of performance, on the other hand, refers to how well a product or service meets the customer's needs and expectations. Quality of design is the extent to which the design of a product or service meets the desired specifications and requirements. Process leeway refers to the degree of flexibility or tolerance allowed in a process.

Question 13

_______ chart monitors the number of nonconformities units in a subgroup.

Accepted Answer

The answer of _______ chart monitors the number of nonconformities...

Question 14

Which one of the following control charts is designed to control the proportion of nonconforming units?

Accepted Answer

p-charts are designed to control the proportion of nonconforming units in a sample. The chart plots the proportion of nonconforming units in each sample and calculates upper and lower control limits based on the average proportion of nonconforming units.

Question 15

If the process variability steadily increases,we would observe

Accepted Answer

If the process variability steadily increases, we would observe an upward trend on the R-chart. This indicates that the process is becoming more variable over time. An alternating pattern of high value followed by a low value on the R-chart, a gradual funnel pattern either increasing or decreasing, are indicative of other issues in process control.

Question 16

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

Accepted Answer

Common causes of variation are also known as natural or random causes of variation and are inherent to a process. These causes contribute to the expected variation within the process and cannot be eliminated entirely.

Question 17

If a control chart is used correctly,and the necessary corrective actions are taken,as the control limits get _______,the potential quality of the product _____________.

Accepted Answer

As the control limits get tighter, it means that the process is becoming more stable and predictable. This leads to a decrease in the variation and an increase in the potential quality of the product. Tight control limits indicate that less variation is acceptable, and any deviations from the expected performance are immediately detected and corrected. Therefore, the correct answer is C.

Question 18

When a process is influenced only by common causes of variation:

Accepted Answer

When a process is influenced only by common causes of variation, it means that the process is in statistical control. This is because common causes of variation are inherent to the process and can be predicted, while assignable causes of variation are not inherent and can be controlled or eliminated. A process that is in statistical control is stable and predictable and has only random variation, which means that the process is capable of meeting customer requirements. However, this does not mean that the process will always meet customer requirements, as there may be other factors outside of the control of the process that can affect customer satisfaction.

Question 19

How well the design of a product or service meets and exceeds the needs and expectations of the customer is called

Accepted Answer

Quality of design refers to how well a product or service has been designed to meet the needs and expectations of the customer. It encompasses the features, functionality, usability, and aesthetics of the product or service. Quality of design is essential in ensuring customer satisfaction and loyalty, as well as differentiation from competitors. Therefore, it is the best choice among the options given.

Question 20

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 or s chart.

Accepted Answer

It is not possible to determine whether it is important or necessary to use an R or s chart based solely on the identification number of a chart used for a given process. The decision to use an R or s chart would depend on the specific characteristics of the measurement data and the quality control objectives of the company.

Quiz 17: Process Improvement Using Control Charts