Lean Six Sigma Black Belt Certification Lean Six Sigma Black Belt Certification-FREE Lean Six Sigma Black Belt Certification 1 — Questions and Answers
Question 1: Which tool is used in the Measure phase to visually display the frequency distribution of a continuous data set?
- Pareto chart
- Histogram (Correct answer)
- Control chart
- Scatter diagram
Correct answer: Histogram
A histogram displays the distribution of continuous data across intervals, making it the primary tool in the Measure phase for understanding data shape, spread, and central tendency before moving to analysis.
Question 2: What is the primary objective of a Gage R&R study in Lean Six Sigma?
- To identify the root cause of defects
- To evaluate the measurement system's repeatability and reproducibility (Correct answer)
- To calculate process capability
- To map the value stream
Correct answer: To evaluate the measurement system's repeatability and reproducibility
Gage R&R (Repeatability and Reproducibility) quantifies variation contributed by the measurement system itself — separating equipment variation from operator variation — to confirm the measurement system is reliable before collecting process data.
Question 3: In hypothesis testing, a Type II error occurs when:
- The null hypothesis is rejected when it is actually true
- The null hypothesis is accepted when it is actually false (Correct answer)
- The p-value exceeds the significance level alpha
- The sample size is too large
Correct answer: The null hypothesis is accepted when it is actually false
A Type II error (also called a false negative or beta error) occurs when the null hypothesis is incorrectly retained even though the alternative hypothesis is true — meaning a real effect goes undetected.
Question 4: Which Lean concept focuses on producing only what is needed, when it is needed, and in the amount needed?
- 5S
- Poka-yoke
- Just-in-Time (JIT) (Correct answer)
- Kaizen
Correct answer: Just-in-Time (JIT)
Just-in-Time (JIT) is a core Lean principle aimed at eliminating overproduction waste by synchronizing production flow with actual customer demand, reducing inventory and lead time.
Question 5: What does a Cp value of 1.0 indicate about a process?
- The process is centered and highly capable
- The process spread exactly matches the specification width, with no margin for error (Correct answer)
- The process has a 3.4 DPMO defect rate
- The process mean is centered at the target value
Correct answer: The process spread exactly matches the specification width, with no margin for error
Cp measures the ratio of the specification width to the process spread (6 sigma). A Cp of 1.0 means the process spread exactly fills the specification limits, leaving zero tolerance for centering shifts — a marginally capable process.
Question 6: In a SIPOC diagram, what does the 'I' stand for?
- Improvement
- Inputs (Correct answer)
- Integration
- Indicators
Correct answer: Inputs
SIPOC stands for Suppliers, Inputs, Process, Outputs, and Customers. 'Inputs' refers to the materials, information, and resources fed into the process by the suppliers, providing a high-level view of the entire system.
Lean Six Sigma Black Belt Certification Lean Six Sigma Black Belt Certification-FREE Lean Six Sigma Black Belt Certification 1
Which tool is used in the Measure phase to visually display the frequency distribution of a continuous data set?