Lean Six Sigma Green Belt Certification Assessment 3 — Questions and Answers
Question 1: A team is performing a process assessment and needs to quantify financial impact. Which metric best represents the cost of poor quality (COPQ)?
- Total revenue minus total expenses
- Costs from appraisal, prevention, internal failure, and external failure (Correct answer)
- Only warranty claims and customer returns
- Direct labor costs associated with rework
Correct answer: Costs from appraisal, prevention, internal failure, and external failure
COPQ encompasses all four quality cost categories: prevention costs, appraisal costs, internal failure costs, and external failure costs.
Question 2: When assessing process capability for attribute data, which index is appropriate?
- Cp and Cpk
- DPU and DPMO (Correct answer)
- Pp and Ppk
- R-bar and X-bar
Correct answer: DPU and DPMO
For attribute data (pass/fail, defect counts), DPU (Defects Per Unit) and DPMO (Defects Per Million Opportunities) are the appropriate capability metrics.
Question 3: A Green Belt assesses the output of a brainstorming session. Which tool would best help the team organize a large number of ideas into logical groupings?
- Pareto chart
- Affinity diagram (Correct answer)
- Control chart
- Scatter diagram
Correct answer: Affinity diagram
An affinity diagram organizes large volumes of qualitative ideas or data into natural groupings based on their relationships, making it ideal for processing brainstorming output.
Question 4: During a current-state value stream map assessment, takt time is calculated to be 45 seconds. The cycle time of the bottleneck operation is 60 seconds. What does this assessment reveal?
- The process can meet customer demand with capacity to spare
- The process cannot meet customer demand at the bottleneck (Correct answer)
- The takt time and cycle time are perfectly balanced
- Takt time is irrelevant when cycle time is known
Correct answer: The process cannot meet customer demand at the bottleneck
When cycle time exceeds takt time at any operation, that operation is the bottleneck and the process cannot meet customer demand without improvement.
Question 5: A Green Belt conducts a process walk to assess actual versus documented procedures. This type of assessment is known as a:
- Gemba walk (Correct answer)
- SIPOC review
- Kano analysis
- Value-added ratio calculation
Correct answer: Gemba walk
A Gemba walk involves going to the actual workplace to observe processes firsthand, comparing what actually happens with what is documented or expected.
Question 6: In assessing root causes, a team builds a cause-and-effect matrix. What input data does this tool primarily use?
- Control chart data and run charts
- Customer requirements and process input variables (Correct answer)
- Financial cost data and ROI calculations
- Operator feedback and supervisor interviews only
Correct answer: Customer requirements and process input variables
The cause-and-effect (C&E) matrix correlates process input variables (Xs) against key customer output requirements (Ys) to prioritize which inputs most impact quality.
Question 7: A Green Belt is assessing sample size requirements for a capability study. The team wants 95% confidence with ±5% precision. Increasing the confidence level to 99% while keeping precision constant will:
- Decrease the required sample size
- Keep the required sample size the same
- Increase the required sample size (Correct answer)
- Have no effect since precision is fixed
Correct answer: Increase the required sample size
Higher confidence levels require larger sample sizes to maintain the same precision, as more certainty about the true population parameter demands more data.
Lean Six Sigma Green Belt Certification Assessment 3
A team is performing a process assessment and needs to quantify financial impact.
Which metric best represents the cost of poor quality (COPQ)?