Lean Six Sigma Black Belt Certification FREE Lean Six Sigma Black Belt Certification Prep Questions and Answers 2 — Questions and Answers
Question 1: Which statistical test is most appropriate for comparing means of three or more groups in a Six Sigma project?
- Chi-Square Test
- One-Way ANOVA (Correct answer)
- Two-Sample t-Test
- Mann-Whitney U Test
Correct answer: One-Way ANOVA
One-Way ANOVA is designed to compare means across three or more independent groups to determine if at least one differs significantly.
Question 2: In a DMAIC project, what is the primary purpose of the Control phase?
- Identify the root cause of defects
- Implement the improved process
- Sustain the gains achieved during Improve (Correct answer)
- Collect baseline data on the current process
Correct answer: Sustain the gains achieved during Improve
The Control phase focuses on maintaining improvements through control plans, monitoring systems, and standardized procedures to prevent regression.
Question 3: What does a Cp value of 1.33 indicate about a process?
- The process is not capable of meeting specifications
- The process is marginally capable
- The process is capable with adequate margin (Correct answer)
- The process has excessive variation
Correct answer: The process is capable with adequate margin
A Cp of 1.33 means the specification width is 1.33 times the process spread, indicating the process is capable with a reasonable safety margin.
Question 4: Which tool is used to prioritize potential failure modes based on severity, occurrence, and detection ratings?
- Pareto Chart
- Failure Mode and Effects Analysis (Correct answer)
- Control Chart
- Cause-and-Effect Diagram
Correct answer: Failure Mode and Effects Analysis
FMEA systematically evaluates potential failures by calculating a Risk Priority Number from severity, occurrence, and detection scores to prioritize corrective actions.
Question 5: What is the purpose of a Gage R&R study in the Measure phase?
- To validate the improvement solution
- To assess measurement system variation (Correct answer)
- To determine process capability
- To identify critical-to-quality characteristics
Correct answer: To assess measurement system variation
A Gage R&R study quantifies how much of the observed process variation is attributable to the measurement system versus the actual process.
Question 6: In hypothesis testing, what does a Type II error represent?
- Rejecting a true null hypothesis
- Failing to reject a false null hypothesis (Correct answer)
- Accepting the alternative hypothesis correctly
- Rejecting the alternative hypothesis correctly
Correct answer: Failing to reject a false null hypothesis
A Type II error occurs when you fail to detect a real difference or effect, essentially missing a true signal in the data.
Lean Six Sigma Black Belt Certification FREE Lean Six Sigma Black Belt Certification Prep Questions and Answers 2
Which statistical test is most appropriate for comparing means of three or more groups in a Six Sigma project?