Lean Six Sigma Green Belt DMAIC Certification Exam |
High-Yield Practice QUESTIONs & Detailed Explanations
2026/2027
QUESTION 1
During which DMAIC phase is the Project Charter officially created and
approved by leadership?
• A. Measure
• B. Define
• C. Analyze
• D. Improve
Correct Answer: B. Define
Detailed Rationale: The Define phase establishes the project
foundation, including the business case, problem statement, objective,
scope, and the formal Project Charter signed by the project sponsor.
QUESTION 2
What is the primary purpose of a SIPOC diagram in the Define phase?
• A. To calculate exact statistical standard deviations.
• B. To outline the high-level process boundaries by identifying
Suppliers, Inputs, Process steps, Outputs, and Customers.
• C. To test hypotheses using Minitab.
• D. To document detailed operator work instructions.
,Correct Answer: B. To outline the high-level process boundaries by
identifying Suppliers, Inputs, Process steps, Outputs, and Customers.
Detailed Rationale: A SIPOC diagram keeps the team focused on the
macro level, defining where a process starts and ends and who the key
stakeholders are.
QUESTION 3
How are broad Voice of the Customer (VOC) statements typically
translated into measurable metrics?
• A. By using a Critical-to-Quality (CTQ) tree.
• B. By running a full factorial Design of Experiments.
• C. By calculating DPMO directly without data collection.
• D. By reviewing financial balance sheets.
Correct Answer: A. By using a Critical-to-Quality (CTQ) tree.
Detailed Rationale: A CTQ tree breaks down vague customer
requirements into specific, quantifiable performance standards that the
project can target.
QUESTION 4
Why are operational definitions crucial during the Measure phase data
collection plan?
• A. They ensure that different people collect data consistently
without ambiguity or subjective bias.
• B. They replace the need for statistical software.
• C. They automatically normalize non-normal data.
, • D. They calculate the financial return on investment.
Correct Answer: A. They ensure that different people collect data
consistently without ambiguity or subjective bias.
Detailed Rationale: An operational definition provides clear,
unambiguous criteria for what constitutes a measurement or defect,
eliminating inconsistencies among data collectors.
QUESTION 5
Which type of data is counted in whole numbers or discrete categories
(e.g., pass/fail, number of blemishes)?
• A. Continuous data
• B. Attribute (Discrete) data
• C. Variable data
• D. Normal data
Correct Answer: B. Attribute (Discrete) data
Detailed Rationale: Attribute data represents countable items or
classifications (e.g., yes/no, good/bad), whereas continuous data is
measured on a continuous scale with infinite precision.
QUESTION 6
What is the primary objective of conducting a Measurement System
Analysis (MSA) or Gage 𝑅&𝑅 study?
• A. To determine if the measurement system introduces excessive
variation relative to total process variation.
• B. To fix machine mechanical breakdowns.
, • C. To calculate the takt time of an assembly line.
• D. To write standard operating procedures.
Correct Answer: A. To determine if the measurement system introduces
excessive variation relative to total process variation.
Detailed Rationale: Before analyzing process data, an MSA verifies that
the measurement tool and operators provide accurate and repeatable
readings.
QUESTION 7
What does a process capability index (𝐶𝑝 𝑘) of 1.33 indicate?
• A. The process is completely incapable and failing specifications.
• B. The process meets the minimum standard industry benchmark
capability for a stable, centered process.
• C. The process has reached world-class Six Sigma quality (6.0
level).
• D. The data is non-normal.
Correct Answer: B. The process meets the minimum standard industry
benchmark capability for a stable, centered process.
Detailed Rationale: A 𝐶𝑝 𝑘 of 1.33 corresponds to a 4-sigma quality level
for a one-sided shift, which is a standard acceptance benchmark in
many industries.
QUESTION 8
Which root cause analysis tool categorizes potential causes using the
6Ms (Man, Machine, Material, Method, Measurement,
Milieu/Environment)?
High-Yield Practice QUESTIONs & Detailed Explanations
2026/2027
QUESTION 1
During which DMAIC phase is the Project Charter officially created and
approved by leadership?
• A. Measure
• B. Define
• C. Analyze
• D. Improve
Correct Answer: B. Define
Detailed Rationale: The Define phase establishes the project
foundation, including the business case, problem statement, objective,
scope, and the formal Project Charter signed by the project sponsor.
QUESTION 2
What is the primary purpose of a SIPOC diagram in the Define phase?
• A. To calculate exact statistical standard deviations.
• B. To outline the high-level process boundaries by identifying
Suppliers, Inputs, Process steps, Outputs, and Customers.
• C. To test hypotheses using Minitab.
• D. To document detailed operator work instructions.
,Correct Answer: B. To outline the high-level process boundaries by
identifying Suppliers, Inputs, Process steps, Outputs, and Customers.
Detailed Rationale: A SIPOC diagram keeps the team focused on the
macro level, defining where a process starts and ends and who the key
stakeholders are.
QUESTION 3
How are broad Voice of the Customer (VOC) statements typically
translated into measurable metrics?
• A. By using a Critical-to-Quality (CTQ) tree.
• B. By running a full factorial Design of Experiments.
• C. By calculating DPMO directly without data collection.
• D. By reviewing financial balance sheets.
Correct Answer: A. By using a Critical-to-Quality (CTQ) tree.
Detailed Rationale: A CTQ tree breaks down vague customer
requirements into specific, quantifiable performance standards that the
project can target.
QUESTION 4
Why are operational definitions crucial during the Measure phase data
collection plan?
• A. They ensure that different people collect data consistently
without ambiguity or subjective bias.
• B. They replace the need for statistical software.
• C. They automatically normalize non-normal data.
, • D. They calculate the financial return on investment.
Correct Answer: A. They ensure that different people collect data
consistently without ambiguity or subjective bias.
Detailed Rationale: An operational definition provides clear,
unambiguous criteria for what constitutes a measurement or defect,
eliminating inconsistencies among data collectors.
QUESTION 5
Which type of data is counted in whole numbers or discrete categories
(e.g., pass/fail, number of blemishes)?
• A. Continuous data
• B. Attribute (Discrete) data
• C. Variable data
• D. Normal data
Correct Answer: B. Attribute (Discrete) data
Detailed Rationale: Attribute data represents countable items or
classifications (e.g., yes/no, good/bad), whereas continuous data is
measured on a continuous scale with infinite precision.
QUESTION 6
What is the primary objective of conducting a Measurement System
Analysis (MSA) or Gage 𝑅&𝑅 study?
• A. To determine if the measurement system introduces excessive
variation relative to total process variation.
• B. To fix machine mechanical breakdowns.
, • C. To calculate the takt time of an assembly line.
• D. To write standard operating procedures.
Correct Answer: A. To determine if the measurement system introduces
excessive variation relative to total process variation.
Detailed Rationale: Before analyzing process data, an MSA verifies that
the measurement tool and operators provide accurate and repeatable
readings.
QUESTION 7
What does a process capability index (𝐶𝑝 𝑘) of 1.33 indicate?
• A. The process is completely incapable and failing specifications.
• B. The process meets the minimum standard industry benchmark
capability for a stable, centered process.
• C. The process has reached world-class Six Sigma quality (6.0
level).
• D. The data is non-normal.
Correct Answer: B. The process meets the minimum standard industry
benchmark capability for a stable, centered process.
Detailed Rationale: A 𝐶𝑝 𝑘 of 1.33 corresponds to a 4-sigma quality level
for a one-sided shift, which is a standard acceptance benchmark in
many industries.
QUESTION 8
Which root cause analysis tool categorizes potential causes using the
6Ms (Man, Machine, Material, Method, Measurement,
Milieu/Environment)?
