Lean Six Sigma Yellow Belt Certification The Improve Phase 4 — Questions and Answers
Question 1: A project team brainstorms 15 possible solutions. Which tool would best help them narrow the list to the top 3 for further evaluation?
- Regression analysis
- Multi-voting or prioritization matrix (Correct answer)
- Cause-and-effect diagram
- P-chart
Correct answer: Multi-voting or prioritization matrix
Multi-voting or a weighted prioritization matrix helps teams quickly narrow a large list of options by scoring feasibility and impact.
Question 2: In the context of the Improve phase, what does 'solution scalability' mean?
- The solution can be implemented cheaply
- The solution can be expanded to other areas or processes successfully (Correct answer)
- The solution reduces headcount proportionally
- The solution applies only to the pilot area
Correct answer: The solution can be expanded to other areas or processes successfully
Scalability means the solution works not just in the pilot but can be replicated across similar processes or locations.
Question 3: A team implements a new process and measures a defect rate of 3.2% versus the pre-improvement rate of 6.8%. What type of evidence does this represent?
- Anecdotal evidence
- Quantitative data-based evidence of improvement (Correct answer)
- A hypothesis yet to be tested
- A control limit violation
Correct answer: Quantitative data-based evidence of improvement
Comparing measured defect rates before and after implementation provides quantitative, data-driven evidence of improvement.
Question 4: Which statement about a kaizen event is most accurate?
- It is a multi-month project led exclusively by Black Belts
- It is a focused, short-duration team effort to rapidly improve a specific process (Correct answer)
- It requires complete process redesign using DMAIC
- It is a daily team meeting to review production metrics
Correct answer: It is a focused, short-duration team effort to rapidly improve a specific process
A kaizen event is an intensive, typically 3–5 day workshop where a cross-functional team makes rapid, targeted process improvements.
Question 5: A team wants to reduce defects caused by operator error. Which improvement is most likely to be sustainable long term?
- Posting reminder signs at workstations
- Installing a poka-yoke device that physically prevents the error (Correct answer)
- Sending weekly reminder emails to operators
- Scheduling quarterly retraining sessions
Correct answer: Installing a poka-yoke device that physically prevents the error
Physical poka-yoke devices prevent errors automatically and do not rely on human memory or behavior, making them the most durable solution.
Question 6: After implementing process changes, a team notices some metrics improved while others worsened. What should they do?
- Accept the trade-offs and close the project
- Investigate the unintended consequences and adjust the solution (Correct answer)
- Revert all changes immediately
- Escalate to the sponsor and wait for direction
Correct answer: Investigate the unintended consequences and adjust the solution
Unintended negative consequences must be investigated and addressed before proceeding to ensure the overall system improves.
Question 7: In Lean, which of the following is an example of 'motion' waste?
- Producing more units than customers ordered
- An operator walking across the floor to retrieve a tool not stored at the workstation (Correct answer)
- Waiting for a machine to complete a long cycle
- Transporting materials to a distant storage area
Correct answer: An operator walking across the floor to retrieve a tool not stored at the workstation
Motion waste refers to unnecessary physical movement by people, such as excessive walking due to poor workstation layout.
Lean Six Sigma Yellow Belt Certification The Improve Phase 4
A project team brainstorms 15 possible solutions.
Which tool would best help them narrow the list to the top 3 for further evaluation?