# Free Six Sigma Black Belt Exam Review

Six Sigma is a philosophy developed for the management of highly complex business and manufacturing enterprises. The Six Sigma Black Belt certification process consists of questions about the Six Sigma philosophy and organizational goals, measurement and key profit drivers, the implementation of lean concepts into manufacturing, and the elimination of obstacles that can derail progress.

A second section of the Six Sigma examination consists of questions within the general category of operations management. This component of the exam requires the test taker to analyze customer data using graphs and statistical tools, to identify degrees of involvement in a process, and to be familiar with quality control techniques related to customer satisfaction.

There are nine questions in the first section of the certification test. These are devoted to the philosophy of Six Sigma; the integration of lean; the interrelationship between operational activities like production, accounting, and design; and the impact this interaction can have on profit. The nine questions in this section focus also upon the leadership that management must provide in setting the direction for structural, cultural, and operational goals. This section of the test requires the student to understand the roles of various Six Sigma levels.

There are also nine questions on the process management aspects of the business enterprise, requiring the test taker to understand and apply Six Sigma concepts to customer satisfaction, quality and cost control, safety, and product delivery. This section of the certification test entails benchmarking, or business performance measurement in the financial and quality areas. In the financial area, test takers may be asked to answer questions about market share, ROI, revenue growth, cost-benefit analysis, and related material.

Sixteen questions are focused on team formation and team management. To succeed in this area, the test taker will need knowledge of team motivation and communication techniques; time management; and performance evaluation.

Fifteen questions ask for definitions of the customer, customer requirements and feedback, the project charter, and tracking by means of schedules and Gantt charts. Twenty-six questions deal with statistical measurement of all operational and process-management activities, while another 24 questions relate to analysis of multivariate tools, regression, and correlation coefficient and hypothesis testing.

Process improvement is the focus of the next 23 questions of the certification test. Test takers must be familiar with concepts of waste elimination, cycle-time reductions, project design, and risk analysis. Finally, there are 21 questions about process control and other control tools.

## Free Six Sigma Black Belt Practice Test Questions

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1. Which type of chart is appropriate when sample size is variable and each sample may contain more than one instance of the targeted condition?
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a. P chart

b. Autocorrelation chart

c. U chart

d. X-bar chart

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2. What is the purpose of PERT analysis during the analyze phase of DMAIC?
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a. To identify the most influential steps in a process

b. To monitor improvements in cycle time

c. To identify the critical path of a process

d. To reduce cycle time

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3. Which form of leveling typically includes the use of heijunka boxes?
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a. Leveling by volume

b. Leveling by product

c. Demand leveling

d. Customer leveling

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4. In response surface analysis, which of the following values for s and t weights would indicate that the upper and lower boundaries are more important than the target?
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a. -0.3

b. 0

c. 1

d. 7

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5. In an analysis of variance, how is the F statistic used?
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a. To compare the mean square treatment with the mean square error

b. To estimate the process average

c. To find the variation within each subgroup

d. To find the variation between different subgroups

## Answers & Explanations

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1. C:** A *U chart* is appropriate when sample size is variable and each sample may contain more than one instance of the targeted condition. These are control charts most appropriate for handling attributes data. A *P chart*, on the other hand, is better for measuring the percentage of samples with a particular characteristic when sample size is variable and the characteristic will either be present or absent. An *autocorrelation chart* indicates the relationships between various factors in the process. An *X-bar chart*, finally, is a control chart for variables data, in which the subgroup averages are assessed to determine the process location variation over time.

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2. C:** The purpose of program evaluation and review techniques (PERT) analysis during the analyze phase of DMAIC is to identify the critical path of a process. PERT analysis uses activity network diagrams and other charts to isolate the tasks on the critical path. Note that the critical path is the sequence of necessarily consecutive steps in a task, such that the sum of the durations required for each step on the critical path will be the minimum amount of time required for the total process. PERT analysis may also be used to identify the most influential steps in a process, though this takes place during the define stage of DMAIC: Likewise, PERT analysis may be used during the improve stage to monitor adjustments to cycle time. The overarching goal of PERT analysis is to reduce cycle time, but this answer choice is too general to be correct.

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3. B:** Leveling by product typically includes the use of heijunka boxes. A *heijunka* box is a tool for scheduling in which the tasks to be completed and the estimated times for initiation and completion are listed. The point of leveling by product is to reduce inefficiency by adjusting the mix of products or the order in which they are produced. Leveling by volume, by contrast, is an approach to reducing inefficiency in which production is aligned with average demand. Demand leveling is a series of strategies that attempt to make customer demand more uniform and predictable. There is no such thing as customer leveling.

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4. D:** In response surface analysis, values of 7 for the *s* and *t* weights would indicate that the upper and lower boundaries are more important than the target. In phase 2 of response surface analysis, the *s* and *t* weights are based on the relationship between the target and the boundary. When the target and the boundary have equal value, the *s* and *t* weights are 1. When the target is more important than the boundary, the *s* and *t* weights are between 1 and 10. When the boundary is more important than the target, the *s* and *t* weights are between 0.1 and 1.

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5. A:** In an analysis of variance, the *F statistic* is used to compare the *mean square treatment* with the mean square error. The mean square treatment is the average variation between the subsets, while the *mean square error* is the sum of the squares of the residuals. In order to trust the results of the F statistic, one must assume that the subsets have a normal distribution and unequal variance. The variation within each subgroup is calculated by taking repeated samples from the subgroup. The variation between different subgroups is found by comparing the averages of each subgroup.

Last Updated: 04/17/2017