Lean Six Sigma Green Belt Certification Improve Phase and Solutions 5 — Questions and Answers
Question 1: A Lean Six Sigma team is implementing a solution that changes a critical parameter setting. Which document should be updated FIRST to reflect the new standard?
- Project charter
- Standard operating procedure (SOP) (Correct answer)
- Cause-and-effect diagram
- Affinity diagram
Correct answer: Standard operating procedure (SOP)
The standard operating procedure must be updated first so that all operators follow the new, improved process consistently.
Question 2: What is the primary purpose of a 'confirmation run' after completing a DOE optimization?
- To add more factors to the study
- To verify that the predicted optimal settings actually achieve the expected response in practice (Correct answer)
- To calculate the F-statistic for ANOVA
- To determine the sample size for the control phase
Correct answer: To verify that the predicted optimal settings actually achieve the expected response in practice
A confirmation run tests the recommended optimal factor settings in real conditions to validate that the model predictions hold.
Question 3: Which Lean waste category includes unnecessary movement of people during their work?
- Transport
- Motion (Correct answer)
- Defects
- Waiting
Correct answer: Motion
Motion waste refers to unnecessary movement of people (e.g., walking, bending, reaching), while transport refers to the unnecessary movement of materials.
Question 4: In the context of solution implementation, 'force field analysis' is used to:
- Identify the root causes of a problem using fishbone logic
- Identify driving forces that support change and restraining forces that oppose it (Correct answer)
- Rank solutions by their return on investment
- Map the current state process flow
Correct answer: Identify driving forces that support change and restraining forces that oppose it
Force field analysis identifies the forces driving a change and those restraining it, helping teams strengthen drivers and reduce barriers.
Question 5: A team wants to reduce changeover time using SMED. After converting internal to external tasks, what is the next SMED step?
- Eliminate the product entirely
- Streamline all remaining internal and external setup activities (Correct answer)
- Increase batch sizes to offset changeover costs
- Move to a single-shift operation
Correct answer: Streamline all remaining internal and external setup activities
After separating and converting setup activities, SMED's next step is to streamline (simplify and standardize) both internal and external tasks to further reduce time.
Question 6: Which improvement strategy focuses on eliminating steps that do not add value from the customer's perspective?
- Statistical process control
- Value-added flow analysis (Correct answer)
- Hypothesis testing
- Gage R&R study
Correct answer: Value-added flow analysis
Value-added flow analysis (value stream analysis) distinguishes value-added from non-value-added steps, targeting the latter for elimination.
Question 7: A Green Belt's improvement solution generates $180,000 in annual savings against an implementation cost of $30,000. What is the ROI?
- 500% (Correct answer)
- 600%
- 83%
- 150%
Correct answer: 500%
ROI = (Net Benefit / Cost) × 100 = (($180,000 − $30,000) / $30,000) × 100 = 500%.
Lean Six Sigma Green Belt Certification Improve Phase and Solutions 5
A Lean Six Sigma team is implementing a solution that changes a critical parameter setting.
Which document should be updated FIRST to reflect the new standard?