Lean Six Sigma Yellow Belt Certification General 5 — Questions and Answers
Question 1: Which of the following best describes 'Special Cause Variation'?
- Natural, random variation inherent in every process
- Variation caused by specific, identifiable factors outside normal operation (Correct answer)
- Variation that is always acceptable to the customer
- Variation eliminated by Six Sigma training alone
Correct answer: Variation caused by specific, identifiable factors outside normal operation
Special cause variation arises from specific, unusual factors (equipment failure, material change) and is detected using control charts as points outside control limits.
Question 2: What is the primary goal of the Improve phase in DMAIC?
- Collect and validate process data
- Develop and implement solutions that address root causes (Correct answer)
- Define project scope and goals
- Monitor the process to sustain gains
Correct answer: Develop and implement solutions that address root causes
The Improve phase designs, tests, and implements solutions that directly address the root causes identified in the Analyze phase.
Question 3: A SIPOC diagram helps a team understand a process by mapping:
- Statistical, Inspection, Process, Output, Control elements
- Suppliers, Inputs, Process, Outputs, and Customers (Correct answer)
- Speed, Inventory, People, Operations, and Costs
- Systems, Integration, Performance, Optimization, and Controls
Correct answer: Suppliers, Inputs, Process, Outputs, and Customers
SIPOC provides a high-level view of a process by identifying who supplies inputs, what the process steps are, and who receives the outputs.
Question 4: What does 'Cycle Time' refer to in process improvement?
- The time from a product's conception to its retirement
- The total time to complete one unit or transaction from start to finish (Correct answer)
- The time between scheduled maintenance cycles
- The time required to train a new team member
Correct answer: The total time to complete one unit or transaction from start to finish
Cycle Time is the total elapsed time to complete one cycle of a process, including both value-added and non-value-added steps.
Question 5: What is the purpose of a 'Pilot' in the Improve phase?
- To fully deploy the solution across the entire organization immediately
- To test a proposed solution on a small scale before full implementation (Correct answer)
- To identify root causes through limited data collection
- To present final results to executive leadership
Correct answer: To test a proposed solution on a small scale before full implementation
A pilot tests the solution in a limited, controlled environment to validate effectiveness and identify issues before organization-wide rollout.
Question 6: In Lean Six Sigma, 'Benchmarking' refers to:
- Setting internal targets based on last year's performance
- Comparing your process performance against industry best practices or competitors (Correct answer)
- Measuring the height of equipment on a factory floor
- Calculating the sigma level of a process
Correct answer: Comparing your process performance against industry best practices or competitors
Benchmarking compares an organization's processes and performance metrics to industry bests or competitors to identify improvement opportunities.
Question 7: Which metric represents the percentage of time a process produces defect-free output on the first attempt without rework?
- Defects Per Million Opportunities (DPMO)
- First Pass Yield (FPY) (Correct answer)
- Overall Equipment Effectiveness (OEE)
- Cost of Poor Quality (COPQ)
Correct answer: First Pass Yield (FPY)
First Pass Yield measures the proportion of units that complete a process correctly the first time, without rework or repair.
Lean Six Sigma Yellow Belt Certification General 5
Which of the following best describes 'Special Cause Variation'?