Practice Exam Questions And Correct

Certified Six Sigma Black Belt (CSSBB) Practice Exam Questions And Correct Answers (Verified Answers) Plus Rationales 2026 Q&A | Instant Download Pdf

• Which phase of DMAIC focuses on defining the project goals and

customer deliverables?

• Measure
• Analyze
• Define
• Control

Rationale: The Define phase establishes the project purpose, scope,

and objectives, and identifies customer requirements.

• Which tool is commonly used in the Measure phase to assess process

capability? 1 / 4

• Cause-and-effect diagram
• FMEA
• Control chart
• Affinity diagram

Rationale: Control charts are used to measure process stability and

capability during the Measure phase.

• In Six Sigma, what is the standard defect rate for a process operating

at “Six Sigma” level?

• 3.4 defects per 1,000 units
• 3.4 defects per million opportunities
• 34 defects per million opportunities
• 0 defects per million opportunities

Rationale: Six Sigma targets 3.4 defects per million opportunities,

representing near-perfect process performance.

• Which type of data represents categories with no intrinsic order?
• Nominal
• Ordinal
• Interval
• Ratio

Rationale: Nominal data are categorical without a natural order,

e.g., types of defects.

• Which statistical test is appropriate for comparing the means of two

independent groups? 2 / 4

• Chi-square test
• t-test
• ANOVA
• Regression

Rationale: A t-test compares the means of two independent samples

to determine if they are significantly different.

• In a SIPOC diagram, what does “C” represent?
• Customers
• Control
• Customers
• Constraints

Rationale: SIPOC stands for Suppliers, Inputs, Process, Outputs,

Customers; “C” represents Customers.

• What is the primary goal of process mapping?
• Increase customer satisfaction
• Understand and visualize process steps
• Reduce defects
• Control variation

Rationale: Process mapping helps identify each step and flow of a

process to find improvement opportunities.

• Which of the following is a key element of Lean methodology?
• Defects per million
• Elimination of waste 3 / 4

• Regression analysis
• Hypothesis testing

Rationale: Lean focuses on removing non-value-added activities,

known as waste, to improve efficiency.

• A project team is performing a root cause analysis. Which tool is most

suitable?

• Control chart
• Scatter plot
• Fishbone diagram
• Pareto chart

Rationale: Fishbone (Ishikawa) diagrams help identify potential

causes of a problem systematically.

• Which measure indicates process capability relative to

specification limits?

• P-value
• Standard deviation
• Cp and Cpk
• Regression coefficient

Rationale: Cp and Cpk measure how well a process can produce

outputs within specification limits.

• Which Six Sigma metric evaluates defects relative to

opportunities for error?

• Sigma level
• / 4