Question 1

You have been given the following sample information that has been drawn from the last sample taken: Mean of the sample: 13.67
Lower control limit for the range: 0
Upper control limit for the range: 10.6
Observations: 13,12,8,10,11,16,17,8,17,18,20,14
Which of the following conclusions does this data support?
A)The process is under control.
B)The process is not under control.
C)The sample is within specifications.
D)The sample is out of specification.

Accepted Answer

D

Question 2

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.What is C_pk? A)0.81 B)1.01 C)0.33 D)1.34 E)0.80

Accepted Answer

The process capability index, $C_{pk}$, is calculated using the formula: $$C_{pk} = \min\left(\frac{USL - \mu}{3\sigma}, \frac{\mu - LSL}{3\sigma}\right)$$ where $USL$ is the upper specification limit, $LSL$ is the lower specification limit, $\mu$ is the process mean, and $\sigma$ is the process standard deviation. Given $USL = 10.5$ mm, $LSL = 9.5$ mm, $\mu = 10.1$ mm, and $\sigma = 0.1$ mm, we calculate: $$C_{pk} = \min\left(\frac{10.5 - 10.1}{3 \times 0.1}, \frac{10.1 - 9.5}{3 \times 0.1}\right) = \min\left(1.33, 2.00\right) = 1.33$$ Rounding to two decimal places, the closest answer is 1.34.

Question 3

Hugging in a control chart usually indicates:
A)The process is out of control.
B)Systematic problems in the process that require attention.
C)The process is in control.
D)Something is occurring that is masking natural variation.

Accepted Answer

Hugging in a control chart suggests that the data points are too close to the center line, indicating that something might be masking the natural variation in the process.

Question 4

Which of the following categories of causes would be most appropriate for a Marriott (an international hotel chain)or McDonalds (an international fast food chain)or the local hair stylist?
A)People,Machine/Equipment,Methods/Processes,Materials
B)Machine,Method,Material,Manpower/Mindpower,Measurement,Mother Nature
C)Product,Price,Place,Promotion,People/personnel,Process,Physical evidence
D)People,Price,Machine,Materials,Mother Nature

Accepted Answer

The category of causes most appropriate for Marriott, McDonalds, and the local hair stylist would be the marketing mix or the 7Ps: product, price, place, promotion, people/personnel, process, and physical evidence. This is because these businesses are in the service industry and need to focus on meeting the needs of their customers by providing quality services in a customer-friendly environment. The 7Ps help them achieve this goal by providing a framework for understanding and optimizing all aspects of the customer experience, from the products and services offered to the way they are priced, promoted, and delivered.

Question 5

Suppose that you are a process manager in a manufacturing plant,and you suspect that there is a relationship between the room temperature of the plant and the weights of the plastic caps produced by an injection molding process.What quality improvement tool would you use to investigate this claim?
A)Fishbone diagram
B)Check list
C)Pareto analysis
D)Histogram
E)Scatter diagram

Accepted Answer

A scatter diagram is the best tool for investigating the relationship between two variables, such as room temperature and plastic cap weight, as it allows the analyst to visually observe the pattern of the data points and determine if a correlation exists. The other quality improvement tools listed are useful for different types of analysis, but do not specifically address this type of relationship.

Question 6

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.The process can be characterized as:
A)Capable.
B)Unreliable.
C)Just barely capable.
D)Out of control.

Accepted Answer

The process is capable because the actual average (10.1 mm) is within the specified limits (9.5 mm to 10.5 mm) and the small standard deviation (0.1 mm) indicates that the process is consistently producing parts close to the target measurement.

Question 7

You have been given the following data: Specification information: Anything between 10 and 20 units per order is acceptable.
Process Mean: 13
Upper limit of the process: 16
Lower limit of the process: 10
Using this information,which of the following conclusions is most appropriate?
A)The process is not capable since it is not centered.
B)The process is barely capable and not centered.
C)The process is capable and centered.
D)The process is not capable and centered.

Accepted Answer

The process mean (13) is not centered within the specification limits (10 to 20), and the process limits (10 to 16) do not fully cover the specification range, indicating the process is barely capable and not centered.

Question 8

The objective of statistical process control (SPC)is to:
A)Determine whether a batch of raw materials should be accepted or rejected.
B)Determine whether a batch of finished goods should be accepted or rejected.
C)Detect assignable cause variations versus normal random variations in the process.
D)Identify variable versus attribute measures.

Accepted Answer

The objective of SPC is to detect assignable cause variations versus normal random variations in the process. SPC involves collecting data on a process over time and using statistical methods to analyze the data to determine if the process is in control (i.e., it is producing products with consistent quality) or if there are assignable causes of variation that need to be addressed. SPC is used to monitor the performance of a process and make adjustments as necessary to ensure that it is producing products that meet specifications. SPC is not used to determine whether a batch of raw materials or finished goods should be accepted or rejected, nor is it used to identify variable versus attribute measures.

Question 9

You are given the following data for taillight assemblies: Which of the following tools does this data represent? A)C_p/C_pk analysis B)Histogram C)Control chart D)Check sheet

Accepted Answer

The given data is in the format of a check sheet, which is used to collect and record data in a structured manner.

Question 10

Which of the following tools is most appropriate when we are interested in determining if a process that was generating attribute-type data (pass/fail,good/bad)was under control?
A)p control chart
B)control chart
C)Scatterplot
D)Histogram

Accepted Answer

A p control chart is the most appropriate tool when we are interested in determining if a process that was generating attribute-type data (pass/fail, good/bad) was under control. This chart tracks the proportion of items in a sample that meets a specific criterion or standard. It can identify if the process is stable or unstable based on the proportion of items that meet the standard in each sample. The chart can determine if the process is in control, out of control, or needs adjustment. Therefore, option A is the best choice in this scenario.

Question 11

Sample means and ranges were obtained for five samples of 10 units per sample from a production process.Assume the process was considered to be in control during the period these samples were collected.The results are as follows:  What is the central line of the X chart for this process
A)10.00
B)10.05
C)10.20
D)9.45
E)9.75

Accepted Answer

The answer of Sample means and ranges were obtained for...

Question 12

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.What is the process capability as measured by C_p? A)0.84 B)1.67 C)0.60 D)1.00 E)1.01

Accepted Answer

The process capability index (Cp) is calculated using the formula: Cp = (USL - LSL) / (6σ), where USL is the upper specification limit, LSL is the lower specification limit, and σ is the standard deviation. Here, USL = 10.5 mm, LSL = 9.5 mm, and σ = 0.1 mm. Thus, Cp = (10.5 - 9.5) / (6*0.1) = 1 / 0.6 = 1.67.

Question 13

The two types of data involved in quality control are:
A)Assignable factors and random factors.
B)Variables and attributes.
C)Random measurements and 100 percent measurements.
D)Accuracy and precision.

Accepted Answer

The two types of data involved in quality control are variables and attributes.

- Variables refer to a measurable quantity that can take on different values, such as weight, length, or temperature. These are typically quantitative data and are often used in statistical process control (SPC) to monitor and improve processes. 
- Attributes, on the other hand, refer to a quality or characteristic that a product or service either has or does not have. Examples of attributes include color, shape, texture, or presence of defects. These are typically qualitative data and are often used in acceptance sampling to determine whether a batch or lot of products is acceptable or not.

While assignable and random factors are important concepts in quality control, they are not the two types of data. Random measurements and 100 percent measurements are not common terms in quality control. Accuracy and precision, while related to quality control, are not types of data but rather measures of quality.

Question 14

A firm has an existing process that it would like to use for producing a part it will sell to an industrial customer.The customer requires that defective (out of specification)parts be kept to 3,000 parts per million (three-tenths of 1 percent)or less.A process capability study done on the process revealed that it has a process capability index (C_pk)of 1.00 for this part.What should the firm conclude from the study? A)The process is not capable,but with careful process control,it could be used to meet the customer's requirements. B)The process is highly capable,and when operating in control,a very high percentage of output will meet the customer's requirements. C)The process is not capable,and even with careful control,it will not be able to meet the customer's requirements. D)The process is capable,but just barely,and will require careful monitoring in order to meet customer requirements.

Accepted Answer

A process capability index (Cpk) of 1.00 indicates that the process mean is exactly 3 standard deviations away from the nearest specification limit. This means the process is capable of meeting the specifications, but there is little room for error, hence it will require careful monitoring to ensure that it continues to meet the customer's requirement of less than 3,000 defective parts per million.

Question 15

Zanda Corp.has determined that it has too many products returned from customers.Zanda is interested in determining what factors or elements could contribute to the large number of returns.Which of the following quality tools would Zanda use to achieve this objective?
A)Process flowchart
B)Pareto analysis
C)Fishbone diagram
D)Run diagram
E)Scatter diagram

Accepted Answer

The fishbone diagram (also known as Ishikawa diagram or cause-and-effect diagram) is a quality tool that helps identify and analyze the potential causes of a problem. It helps break down the problem into smaller components and examine how each component might contribute to the problem. Zanda can use the fishbone diagram to explore and identify the reasons for the high number of product returns, such as manufacturing defects, poor product design, inadequate packaging, or unclear instructions. By identifying the root causes of the problem, Zanda can take corrective action to reduce the number of returns and improve customer satisfaction.

Question 16

The Taguchi methods link product design to:
A)Customer expectations.
B)Production availability.
C)Process improvement.
D)Unexplained variance.

Accepted Answer

The Taguchi methods focus on improving the quality of products by optimizing the design and manufacturing processes, which is a form of process improvement.

Question 17

You are involved in the implementation of a quality improvement program.Your immediate goal is to identify what problems you should focus on (ideally you want to focus on those that give you the biggest bang for the buck).Which of the following quality control procedures is the most appropriate?
A)Fishbone diagrams
B)Process flow charts
C)Pareto analysis
D)Histograms

Accepted Answer

Pareto analysis is the most appropriate quality control procedure for identifying which problems to focus on because it allows you to prioritize problems based on their frequency and impact. The Pareto principle states that 80% of the effects come from 20% of the causes, so by identifying the top 20% of problems, you can focus your efforts on those that will have the biggest impact on improving quality. Fishbone diagrams, process flow charts, and histograms are useful for analyzing specific problems once they have been identified, but they do not provide a prioritization of problems.

Question 18

The width of a histogram showing a distribution of data indicates the __________ of the process that generated the distribution.
A)Predictability
B)Average
C)Bias
D)Central tendency

Accepted Answer

The width of a histogram represents the spread or variability of the data. A wider histogram indicates a less predictable process, while a narrower histogram indicates a more predictable process. Therefore, the correct answer is A) Predictability.

Question 19

Sample means and ranges were obtained for five samples of 10 units per sample from a production process.Assume the process was considered to be in control during the period these samples were collected.The results are as follows:  LCL for the three sigma X chart for the process is approximately (for a sample size of 10,A2 = 0.31):
A)10.12.
B)10.05.
C)10.94.
D)9.44.
E)9.75.

Accepted Answer

The answer of Sample means and ranges were obtained for...

Question 20

"Pass/ fail" and "go/no go" are both examples of:
A)Attribute data.
B)Decision data.
C)Process flow data.
D)Variable data.

Accepted Answer

"Pass/fail" and "go/no go" are both examples of attribute data, which is data that is qualitative and can only be described in terms of presence or absence of a characteristic.

Quiz 15: A: Advanced Methods for Project Scheduling

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.What is C_pk?

Hugging in a control chart usually indicates:

Which of the following categories of causes would be most appropriate for a Marriott (an international hotel chain) or McDonalds (an international fast food chain) or the local hair stylist?

Suppose that you are a process manager in a manufacturing plant,and you suspect that there is a relationship between the room temperature of the plant and the weights of the plastic caps produced by an injection molding process.What quality improvement tool would you use to investigate this claim?

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.The process can be characterized as:

You have been given the following data: Specification information: Anything between 10 and 20 units per order is acceptable. Process Mean: 13 Upper limit of the process: 16 Lower limit of the process: 10 Using this information,which of the following conclusions is most appropriate?

The objective of statistical process control (SPC) is to:

You are given the following data for taillight assemblies: Which of the following tools does this data represent?

Which of the following tools is most appropriate when we are interested in determining if a process that was generating attribute-type data (pass/fail,good/bad) was under control?

Sample means and ranges were obtained for five samples of 10 units per sample from a production process.Assume the process was considered to be in control during the period these samples were collected.The results are as follows: What is the central line of the X chart for this process

The specifications for the diameter of a molded part are 10 mm ± 0.5 mm.The actual average and standard deviation from 250 parts sampled is 10.1 mm and 0.1 mm,respectively.What is the process capability as measured by C_p?

The two types of data involved in quality control are:

Zanda Corp.has determined that it has too many products returned from customers.Zanda is interested in determining what factors or elements could contribute to the large number of returns.Which of the following quality tools would Zanda use to achieve this objective?

The Taguchi methods link product design to:

You are involved in the implementation of a quality improvement program.Your immediate goal is to identify what problems you should focus on (ideally you want to focus on those that give you the biggest bang for the buck) .Which of the following quality control procedures is the most appropriate?

The width of a histogram showing a distribution of data indicates the __________ of the process that generated the distribution.

"Pass/ fail" and "go/no go" are both examples of: