Lean Six Sigma Yellow Belt Certification Assessment 3 — Questions and Answers
Question 1: What type of data is collected when counting the number of scratches on a painted surface?
- Continuous data
- Attribute data (Correct answer)
- Variable data
- Ordinal data
Correct answer: Attribute data
Counting defects (scratches) produces attribute data, which is discrete and counts occurrences rather than measuring a dimension.
Question 2: In a Lean Six Sigma assessment, what does Overall Equipment Effectiveness (OEE) measure?
- The percentage of time a machine is scheduled for maintenance
- The combined impact of availability, performance, and quality on productive output (Correct answer)
- The number of operators required per machine
- Customer satisfaction with equipment output
Correct answer: The combined impact of availability, performance, and quality on productive output
OEE multiplies availability, performance rate, and quality rate to give a single metric of how effectively equipment is being used.
Question 3: Which chart is most appropriate for assessing the proportion of defective items in a process when sample sizes vary?
- c-chart
- p-chart (Correct answer)
- X-bar chart
- R-chart
Correct answer: p-chart
The p-chart tracks the proportion of defective units and accommodates varying sample sizes, making it suitable for attribute data with changing subgroup sizes.
Question 4: A team uses a spaghetti diagram during process assessment. What does this tool primarily reveal?
- Defect frequency by category
- Physical movement and travel paths of people or materials (Correct answer)
- Statistical variation in output
- Customer demand patterns
Correct answer: Physical movement and travel paths of people or materials
A spaghetti diagram traces the physical movement paths in a workspace to identify excessive travel that represents waste.
Question 5: When assessing a process, a team discovers that 80% of defects come from 20% of causes. Which principle does this illustrate?
- Central Limit Theorem
- Pareto Principle (Correct answer)
- Theory of Constraints
- Normal Distribution Rule
Correct answer: Pareto Principle
The Pareto Principle (80/20 rule) states that a small number of causes typically account for the majority of problems or defects.
Question 6: What is the primary purpose of a SIPOC diagram during the Define or Measure phase assessment?
- To calculate defect rates
- To provide a high-level overview of the process including Suppliers, Inputs, Process, Outputs, and Customers (Correct answer)
- To identify the root cause of variation
- To create a control plan
Correct answer: To provide a high-level overview of the process including Suppliers, Inputs, Process, Outputs, and Customers
SIPOC gives the project team and stakeholders a concise, high-level view of the entire process scope before diving into detailed analysis.
Question 7: During an assessment, a team finds that a process has a high Cp but a low Cpk. What does this indicate?
- The process spread is too wide for the specification
- The process is capable but not centered within the specification limits (Correct answer)
- Both the spread and centering are adequate
- The process has no variation
Correct answer: The process is capable but not centered within the specification limits
High Cp means the process spread fits within specs, but low Cpk reveals the process is shifted off-center, producing defects near one specification limit.
Lean Six Sigma Yellow Belt Certification Assessment 3
What type of data is collected when counting the number of scratches on a painted surface?