Question 1

In quality control, the famous business adage is: "If it can't be ____________, it can't be managed"

Accepted Answer

In quality control, the famous business adage is: "If it can't be measured, it can't be managed.
Key Takeaway: Metrics are an important aspect of quality control. Processes cannot be managed effectively if they cannot be measured with accuracy. For example, delays in a production cycle cannot be managed without understanding the steps involved and their durations as well as gaining information about the performance of the machines involved.

Question 2

What two metrics in manufacturing are used to calculate cost of process flows?

Accepted Answer

Quality and cycle time are two metrics used to calculate cost of process flows.
Key Takeaway: In manufacturing, it is important to calculate the cost of process flows, especially when a production cycle contains multiple processes. Quality and cycle time are two metrics that are used to calculate cost of process flows with quality examined in terms of product defects. Cycle time helps shed light on process delays.

Question 3

A Black Belt practitioner leading a team of engineers urges them to devise a statement for their project. A project statement should be SMART. What does the A stand for in this acronym?

Accepted Answer

The A stands for Achievable.
Key Takeaway: The acronym SMART is used to describe an effective project statement that helps team members focus their conception of goals and activities. An effective project statement is Specific, Measurable, Achievable, Relevant and Timely. The goal of using SMART is to encourage concrete goals and activities that can be completed within the allotted time and resources available while being amenable to measurement and evaluation.

Question 4

The Define phase is the first phase of Six Sigma's DMAIC cycle. If this phase is not planned for and carried out thoroughly, a project may stall and not transition to other phases successfully. Which of the following statements is well-defined?

Accepted Answer

'Reduce the reject rate of service B from 30% to 10% within 2 calendar years' is a well-defined project statement.
Key Takeaway: Well-defined project statements are important in that they present a concrete goal that that has a time limit and a measurable outcome. In this example, a period of 2 years provides a guideline for employees to plan their activities to reach this goal while the percentage reduction of 20 is a measurable goal.

Question 5

A relationship matrix matches process ________ and _________.

Accepted Answer

A relationship matrix matches process inputs and outputs.
Key Takeaway: Relationship matrices are used to describe the connection between process inputs and desirable outputs. For example, if an application designer wishes to match available technological expertise to client needs (desirable outputs), a relationship matrix can be used. Teams gather input through brainstorming and other data collection methods in order to match inputs to desirable outputs in a project.

Question 6

Eastern Batteries Inc. distributes battery products to retailers across the continental United States. Sales managers chart monthly sales of different batteries using:

Accepted Answer

Sales managers chart monthly sales of different batteries using frequency tables.
Key Takeaway: Frequency tables provide a visual display of variables such as monthly sales by dividing them into intervals and counting the number of scores or instances in each interval. Frequency tables are used as a basis for the construction of diagrams such as histograms and pie charts.

Question 7

Business professional are interested in collecting data that can be used to predict future sales or customers' behavior. Parameters are characteristics of a _______ while statistics are characteristics of a ________.

Accepted Answer

Parameters are characteristics of a population while statistics are characteristics of a sample.
Key Takeaway: It is important not to confuse a set of data drawn from a population with that of a sample. For example, a principal at a middle school of 500 students can average the ages of all the students which leads to a population parameter. If only students in the sixth grade are included in the calculation of the average, the resulting figure is a sample statistic.

Question 8

Which of the following descriptive statistic uses (?) for a population and (s) for a sample?

Accepted Answer

Standard deviation uses (?) for a population and (s) for a sample.
Key Takeaway: Standard deviation is a descriptive statistic that takes into account how each data point deviates from the average of a data set. Standard deviation is an important measure of data scatter around a mean which is also an important aspect of a process' variation. In Six Sigma methodology, the best way to reduce the inefficiencies of a process is to reduce its variation.

Question 9

A Black Belt practitioner states in a project report that "we are 95% confident that the average age of consumers of Product A are between 34 and 38 years". What does a confidence interval denote?

Accepted Answer

A confidence interval denotes that they are 95% confident about the average age of the population.
Key Takeaway: In the above example, the practitioner is 95% confident that the average age of the population consumers of Product A are between 34 and 38 years. Since the average age is calculated based on a sample and not the population, a confidence level is considered an inferential tool. In other words, an inference or an educated guess is made about the population based on the characteristics of the sample.

Question 10

Weldman Industries conducts a survey which shows that their average production cycle time is 128 minutes with a sampling error of 3 seconds. What does a sampling error result from?

Accepted Answer

A sampling error results from using a sample instead of a population.
Key Takeaway: A sampling error occurs from using a sample to collect date instead of a population to estimate a population parameter. For example, if a company uses a sample of 50 employees (out of a total population of 600), then a sampling error would occur as the estimate can only approximate the population parameter. In general, a sampling error can be reduced by choosing a large, representative sample from which to collect data.

Question 11

According to the Central Limit Theorem, regardless of the population from which data is drawn, the sampling distribution of the mean when sufficiently large is:

Accepted Answer

The sampling distribution of the mean, when sufficiently large, is normally distributed.
Key Takeaway: When a sample is sufficiently large, the distribution around the mean of the data set is said to be normal. The approximation of the sample distribution to that of the population improves as the sample size increases.

Question 12

A company is choosing between 5 different health plans for their employees. To make a decision, they present the value and characteristics of each health plan in a table also referred to as a(an):

Accepted Answer

The value and characteristics of each health plan is displayed in a contingency table.
Key Takeaway: A contingency table (also known as an RxC table) presents information in rows and columns in an effort to have a comparative display of characteristics. For example, the health plans prices can be displayed in one row with each of the five plans in a separate column. This allows the company to quickly and conveniently have a comparative view of the 5 health plans.

Question 13

A Black Belt practitioner at DuPont Industries uses a process map, SIPOC, in his project. What does the P stand for in this acronym?

Accepted Answer

The P stands for Process.
Key Takeaway: Process maps are important in providing a visual guide to all project members about processes, inputs, outputs, and stakeholders. SIPOC stands for Suppliers, Inputs, Process, Output, and Customers. The goal of a SIPOC diagram is to connect a project's inputs and processes with desired outputs that match customers' requirements and needs. Customers can be both internal and external depending on the nature of the output such as reports, products, or services.

Question 14

A plant manager notices a high variation in output quality from 8 machines within one production cycle. He collects the average defects per total output for each machine per hour. As a variable, output defects is:

Accepted Answer

As a variable, output defects is critical to quality (CTQ).
Key Takeaway: In quality control, a business manager must collect relevant data and calculate a sample statistic in order to compare subgroups. In this example, the 8 machines are subgroups while the defects per total output provides a variable that is critical to quality (or CTQ). This comparison allows the manager to address the variations in quality and make recommendations such as replacing the faulty machines.

Question 15

A Black Belt practitioner is commissioned to examine the reason adjustments to common cause variations are not leading to a reduction in variation. She finds that common cause variations are treated as special variations which is also called:

Accepted Answer

Tampering occurs when common cause variations are treated as special variations.
Key Takeaway: Common cause variations in process efficiency such as those attributed to machines and people skills should not be treated as special (unusual variations) as this results in tampering with the processes. Tampering does not lead to a reduction in variation and may cause them to increase. To avoid tampering, quality control charts should be used.

Question 16

A special cause variation has the following qualities EXCEPT:

Accepted Answer

Variations in tools are not special cause variations.
Key Takeaway: Variations that result from machines, tools, materials, operators, and the environment are not considered special cause ones. Special cause variations are abnormal or unexpected and have an assignable cause. They are also not inherent to the process involved.

Question 17

Jamieson Inc. produces self-cleaning commercial ovens. In the testing phase of this capability, 20 tests were conducted on the prototype and the results show that 10 consecutive results show process variability that is below the given mean. Is this process in-control or out-of-control?

Accepted Answer

This process is out-of-control.
Key Takeaway: A process is said to be out-of-control 8 or more data points lie consecutively on one side of the mean in the control chart. A process is also said to be out-of-control if one or more points fall outside the control limits (i.e. above the UCL or below the LCL).

Question 18

Process capability (Cp) describes a process, often in a stable manufacturing environment, that leads to the production of a product that conforms to client and design specifications. An ideal process will have a Cp value:

Accepted Answer

An ideal process will have a Cp value that is greater than one.
Key Takeaway: An ideal process, usually in a stable manufacturing environment will have a Cp value that is greater than one. This means that the process of three-sigma limit is contained within both the client and the design specification.

Question 19

RBC Inc. produces rods for construction clients. A client requests metal rods that are 20 inches ± 0.02 inches. The manufacturing process has a sigma of 0.004. What is the process capability (C_P) of this process?

Accepted Answer

The process capability (C_P) is 1.67. Key Takeaway: A process capability value greater than one implies that the process of three-sigma limit is contained within the client specification. To calculate the C_P, the following equation is used: C_P = (USL - LSL)/ 6? C_P = (0.02 + 0.02)/ 6(0.004) C_P = 1.67

Question 20

Which of the control charts must have at least 20 subgroups of observed values to judge whether a process is in control or not?

Accepted Answer

An R-chart must have at least 20 subgroups of observed values to judge whether a process is in control or not.
Key Takeaway: An R-chart contains data collected from a business or industrial process at regular intervals. It measures the sample range over time which is a measure of dispersion. An R-chart must have at least 20 subgroups of observed values with each subgroup containing 3 to 6 observations. This minimum number of observations allows a manager to observe whether the variation falls within the upper and lower control limits.

Quiz 1: Black Belt

In quality control, the famous business adage is: "If it can't be ____________, it can't be managed"

What two metrics in manufacturing are used to calculate cost of process flows?

A Black Belt practitioner leading a team of engineers urges them to devise a statement for their project. A project statement should be SMART. What does the A stand for in this acronym?

The Define phase is the first phase of Six Sigma's DMAIC cycle. If this phase is not planned for and carried out thoroughly, a project may stall and not transition to other phases successfully. Which of the following statements is well-defined?

A relationship matrix matches process and _.

Eastern Batteries Inc. distributes battery products to retailers across the continental United States. Sales managers chart monthly sales of different batteries using:

Business professional are interested in collecting data that can be used to predict future sales or customers' behavior. Parameters are characteristics of a _ while statistics are characteristics of a __.

Which of the following descriptive statistic uses (?) for a population and (s) for a sample?

A Black Belt practitioner states in a project report that "we are 95% confident that the average age of consumers of Product A are between 34 and 38 years". What does a confidence interval denote?

Weldman Industries conducts a survey which shows that their average production cycle time is 128 minutes with a sampling error of 3 seconds. What does a sampling error result from?

According to the Central Limit Theorem, regardless of the population from which data is drawn, the sampling distribution of the mean when sufficiently large is:

A company is choosing between 5 different health plans for their employees. To make a decision, they present the value and characteristics of each health plan in a table also referred to as a(an) :

A Black Belt practitioner at DuPont Industries uses a process map, SIPOC, in his project. What does the P stand for in this acronym?

A plant manager notices a high variation in output quality from 8 machines within one production cycle. He collects the average defects per total output for each machine per hour. As a variable, output defects is:

A Black Belt practitioner is commissioned to examine the reason adjustments to common cause variations are not leading to a reduction in variation. She finds that common cause variations are treated as special variations which is also called:

A special cause variation has the following qualities EXCEPT:

Jamieson Inc. produces self-cleaning commercial ovens. In the testing phase of this capability, 20 tests were conducted on the prototype and the results show that 10 consecutive results show process variability that is below the given mean. Is this process in-control or out-of-control?

Process capability (Cp) describes a process, often in a stable manufacturing environment, that leads to the production of a product that conforms to client and design specifications. An ideal process will have a Cp value:

RBC Inc. produces rods for construction clients. A client requests metal rods that are 20 inches ± 0.02 inches. The manufacturing process has a sigma of 0.004. What is the process capability (C_P) of this process?

Which of the control charts must have at least 20 subgroups of observed values to judge whether a process is in control or not?

Quiz 1: Black Belt

In quality control, the famous business adage is: "If it can't be ____________, it can't be managed"

What two metrics in manufacturing are used to calculate cost of process flows?

A Black Belt practitioner leading a team of engineers urges them to devise a statement for their project. A project statement should be SMART. What does the A stand for in this acronym?

The Define phase is the first phase of Six Sigma's DMAIC cycle. If this phase is not planned for and carried out thoroughly, a project may stall and not transition to other phases successfully. Which of the following statements is well-defined?

A relationship matrix matches process ________ and _________.

Eastern Batteries Inc. distributes battery products to retailers across the continental United States. Sales managers chart monthly sales of different batteries using:

Business professional are interested in collecting data that can be used to predict future sales or customers' behavior. Parameters are characteristics of a _______ while statistics are characteristics of a ________.

Which of the following descriptive statistic uses (?) for a population and (s) for a sample?

A Black Belt practitioner states in a project report that "we are 95% confident that the average age of consumers of Product A are between 34 and 38 years". What does a confidence interval denote?

Weldman Industries conducts a survey which shows that their average production cycle time is 128 minutes with a sampling error of 3 seconds. What does a sampling error result from?

According to the Central Limit Theorem, regardless of the population from which data is drawn, the sampling distribution of the mean when sufficiently large is:

A company is choosing between 5 different health plans for their employees. To make a decision, they present the value and characteristics of each health plan in a table also referred to as a(an) :

A Black Belt practitioner at DuPont Industries uses a process map, SIPOC, in his project. What does the P stand for in this acronym?

A plant manager notices a high variation in output quality from 8 machines within one production cycle. He collects the average defects per total output for each machine per hour. As a variable, output defects is:

A Black Belt practitioner is commissioned to examine the reason adjustments to common cause variations are not leading to a reduction in variation. She finds that common cause variations are treated as special variations which is also called:

A special cause variation has the following qualities EXCEPT:

Jamieson Inc. produces self-cleaning commercial ovens. In the testing phase of this capability, 20 tests were conducted on the prototype and the results show that 10 consecutive results show process variability that is below the given mean. Is this process in-control or out-of-control?

Process capability (Cp) describes a process, often in a stable manufacturing environment, that leads to the production of a product that conforms to client and design specifications. An ideal process will have a Cp value:

RBC Inc. produces rods for construction clients. A client requests metal rods that are 20 inches ± 0.02 inches. The manufacturing process has a sigma of 0.004. What is the process capability (CP) of this process?

Which of the control charts must have at least 20 subgroups of observed values to judge whether a process is in control or not?

A relationship matrix matches process and _.

Business professional are interested in collecting data that can be used to predict future sales or customers' behavior. Parameters are characteristics of a _ while statistics are characteristics of a __.

RBC Inc. produces rods for construction clients. A client requests metal rods that are 20 inches ± 0.02 inches. The manufacturing process has a sigma of 0.004. What is the process capability (C_P) of this process?