Question 1

Table $7.1$
Factors for Calculating Three- Sigma Limits for the $\overline { \bar { X } }$ - chart and $R$ - chart

-A milling operation has historically produced an average thickness of 0.005 inch with an average range of 0.0015 inch. Currently, the first three items from each batch of 20 are inspected. Use Table 1.. What is the value of the 
$UC L \overline{_\mathrm{X}} ?$

Accepted Answer

D

Question 2

Which one of the following statements about quality control is TRUE?

Accepted Answer

Measurement by attributes involves checking whether each item meets the quality standards, resulting in a simple yes or no decision.

Question 3

Which of the following statements is TRUE?

Accepted Answer

Process capability refers to the ability of a process to produce output within specification limits, which is related to meeting a product's design specifications.

Question 4

Table $7.1$
Factors for Calculating Three- Sigma Limits for the $\overline { \bar { X } }$ - chart and $R$ - chart

-A milling operation has historically produced an average thickness of 0.005 inch with an average range of 0.015 inch. Currently, the first three items from each batch of 20 are inspected. Use Table 7.1 What is the value of the $$L C L \bar { X } ?$$

Accepted Answer

The answer of Table $7.1$
Factors for Calculating Three- Sigma Limits...

Question 5

Which one of the following statements is TRUE?

Accepted Answer

No two products are exactly alike because the processes that produce them contain many sources of variation, even if the process is a machine.

Question 6

Which one of the following is a consequence of external failures?

Accepted Answer

External failures often lead to more litigation costs as they involve defects found after the product has reached the customer, potentially leading to legal actions.

Question 7

Improving quality seems to be a strategic weapon in gaining market share. However, improving quality entails allocation of resources and effort. Which one of the following costs increases to improve quality?

Accepted Answer

Prevention costs increase to improve quality as they involve activities designed to prevent defects and improve product quality, such as training, process improvement, and quality planning.

Question 8

Which one of the following statements regarding customers' definition of quality is FALSE?

Accepted Answer

Conformance to specifications is important for service providers as well, as services have standards and expectations that need to be met to ensure quality.

Question 9

When should complete inspection be used?

Accepted Answer

When the cost of product failure is high relative to the inspection costs, complete inspection is used to ensure that all products meet the required quality standards.

Question 10

A measure of the dispersion of observations in a process distribution is called a(n)

Accepted Answer

The range is a measure of dispersion that indicates the difference between the highest and lowest values in a data set.

Question 11

$$\begin{array}{l}
\text { Table } 7.3\
\begin{array} { | c | l | } 
\hline \text { Sample Number } & \text { Number Defective } \
\hline 1 & 1 \
2 & 4 \
3 & 2 \
4 & 4 \
5 & 0 \
\hline
\end{array}
\end{array}$$
-Use the information from Table 7.3. What is the upper control limit (UCL) if the bank were to use z = 2 and a sample size of 100?

Accepted Answer

The average proportion defective (p-bar) is 0.022. The standard deviation is calculated as sqrt(p-bar(1-p-bar)/n) = sqrt(0.022*0.978/100) = 0.0147. The UCL is p-bar + z*standard deviation = 0.022 + 2*0.0147 = 0.0514, which falls in the range greater than 0.04 but less than or equal to 0.06.

Question 12

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 2- sigma control limit is used, what should be done if a bolt is found with 3 defects?

Accepted Answer

The process is out of control because the number of defects (3) is less than the lower control limit (11 - 2 * 3 = 5). Management should investigate and exploit the assignable causes of variation present to bring the process back into control.

Question 13

The UCL and LCL for an $\bar { X } -$chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 24, and 16. What should you do?

Accepted Answer

The answer of The UCL and LCL for an \(\bar...

Question 14

A company is interested in monitoring the variability in the weight of the fertilizer bags it produces. An appropriate control chart would be

Accepted Answer

The answer of A company is interested in monitoring the...

Question 15

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 3- sigma control limit is desired, what is the lower control limit?

Accepted Answer

The answer of A manufacturer of silk inspects each bolt...

Question 16

Historically, the average time to service a customer complaint has been 3 days and the standard deviation has been 0.50 day. Management would like to specify the control limits for an X- chart with a sample size of 10 and 3 sigma limits. The UCL for the chart would be ---

Accepted Answer

The UCL (Upper Control Limit) for an X-chart is calculated as the average plus 3 times the standard error. The standard error is the standard deviation divided by the square root of the sample size. Here, UCL = 3 + 3*(0.50/√10) = 3 + 0.474 = 3.474, which falls in the range greater than 3.40 but less than or equal to 3.50.

Question 17

Historically, the average proportion of defective bars has been 0.015. Samples will be of 100 bars each. Construct a p- chart using z = 3. Suppose a sample had 0.07 defective. What would you do?

Accepted Answer

The sample proportion of defective bars (0.07) is significantly higher than the historical average (0.015). With z = 3, this indicates the sample is outside the control limits, suggesting an assignable cause rather than random variation.

Question 18

Which one of the following techniques will help management trace customer complaints directly to the operations involved?

Accepted Answer

A cause-and-effect diagram, also known as a fishbone diagram, helps identify the root causes of a problem, such as customer complaints, by tracing them back to specific operations or processes.

Question 19

Which one of the following is a consequence of internal failures?

Accepted Answer

Internal failures often lead to increased inventory costs due to the need to hold more stock to compensate for defects and rework.

Question 20

A hotel tracks the number of complaints per month. When the process is in control, there is an average of 35 complaints per month. Assume that a 2- sigma control limit is used. The next four months have 33, 27, 29, and 43 complaints. What should management do?

Accepted Answer

The number of complaints in each of the four months falls within the 2-sigma control limits around the average of 35 complaints, indicating the process is in control.

Quiz 7: Inventory Management

Which one of the following statements about quality control is TRUE?

Which of the following statements is TRUE?

Which one of the following statements is TRUE?

Which one of the following is a consequence of external failures?

Improving quality seems to be a strategic weapon in gaining market share. However, improving quality entails allocation of resources and effort. Which one of the following costs increases to improve quality?

Which one of the following statements regarding customers' definition of quality is FALSE?

When should complete inspection be used?

A measure of the dispersion of observations in a process distribution is called a(n)

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 2- sigma control limit is used, what should be done if a bolt is found with 3 defects?

The UCL and LCL for an $\bar { X } -$ chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 24, and 16. What should you do?

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 3- sigma control limit is desired, what is the lower control limit?

Historically, the average time to service a customer complaint has been 3 days and the standard deviation has been 0.50 day. Management would like to specify the control limits for an X- chart with a sample size of 10 and 3 sigma limits. The UCL for the chart would be ---

Historically, the average proportion of defective bars has been 0.015. Samples will be of 100 bars each. Construct a p- chart using z = 3. Suppose a sample had 0.07 defective. What would you do?

Which one of the following techniques will help management trace customer complaints directly to the operations involved?

Which one of the following is a consequence of internal failures?

A hotel tracks the number of complaints per month. When the process is in control, there is an average of 35 complaints per month. Assume that a 2- sigma control limit is used. The next four months have 33, 27, 29, and 43 complaints. What should management do?

Quiz 7: Inventory Management

Which one of the following statements about quality control is TRUE?

Which of the following statements is TRUE?

Which one of the following statements is TRUE?

Which one of the following is a consequence of external failures?

Improving quality seems to be a strategic weapon in gaining market share. However, improving quality entails allocation of resources and effort. Which one of the following costs increases to improve quality?

Which one of the following statements regarding customers' definition of quality is FALSE?

When should complete inspection be used?

A measure of the dispersion of observations in a process distribution is called a(n)

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 2- sigma control limit is used, what should be done if a bolt is found with 3 defects?

The UCL and LCL for an Xˉ−\bar { X } -Xˉ− chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 24, and 16. What should you do?

A company is interested in monitoring the variability in the weight of the fertilizer bags it produces. An appropriate control chart would be

A manufacturer of silk inspects each bolt of material at the end of the manufacturing process. When the process is in control, it averages 11 defects per bolt. If a 3- sigma control limit is desired, what is the lower control limit?

Historically, the average time to service a customer complaint has been 3 days and the standard deviation has been 0.50 day. Management would like to specify the control limits for an X- chart with a sample size of 10 and 3 sigma limits. The UCL for the chart would be ---

Historically, the average proportion of defective bars has been 0.015. Samples will be of 100 bars each. Construct a p- chart using z = 3. Suppose a sample had 0.07 defective. What would you do?

Which one of the following techniques will help management trace customer complaints directly to the operations involved?

Which one of the following is a consequence of internal failures?

A hotel tracks the number of complaints per month. When the process is in control, there is an average of 35 complaints per month. Assume that a 2- sigma control limit is used. The next four months have 33, 27, 29, and 43 complaints. What should management do?

The UCL and LCL for an $\bar { X } -$ chart are 25 and 15 respectively. The central line is 20, and the process variability is considered to be in statistical control. The results of the next six sample means are 18, 23, 17, 21, 24, and 16. What should you do?