SIX SIGMA GREEN BELT CERTIFICATION EXAM QUESTIONS COMPLETE WITH 100% CORRECT ANSWERS 2026/2027

SIX SIGMA GREEN BELT CERTIFICATION EXAM QUESTIONS COMPLETE WITH 100% CORRECT ANSWERS Question 1 Which of the following best defines a "Critical to Quality" (CTQ) characteristic? A) A metric tracked only at the project’s closure B) A requirement derived from internal process goals C) A measurable defect that is always binary D) A characteristic that directly impacts customer satisfaction Correct Answer: D Explanation: CTQ characteristics are identified from the Voice of the Customer (VOC) and represent product or service features that have a direct impact on customer satisfaction or dissatisfaction. They are measurable and actionable, not merely internal. ________________________________________ Question 2 In a control chart, which rule suggests an out-of-control process? A) A single point within 1 sigma of the mean B) All points within control limits C) Fifteen points in a row within ±1 sigma of centerline D) A run of 7 points all below the centerline Correct Answer: D *Explanation: A run of 7 consecutive points on the same side of the centerline (above or below) is a Western Electric rule indicating a shift in the process mean, even if all points are within control limits. Fifteen points within ±1 sigma may actually suggest reduced variation but not necessarily out-of-control; seven points in a row below is a signal.* ________________________________________ Question 3 Which Lean tool is most appropriate for reducing waiting time between process steps? A) Poka-Yoke B) Value Stream Mapping C) Control Chart D) FMEA Correct Answer: B Explanation: Value Stream Mapping visually maps material and information flow, highlighting waiting time, non-value-added steps, and inventory buffers. Poka-Yoke prevents errors, FMEA assesses risk, and control charts monitor stability. ________________________________________ Question 4 A process has a Cp of 1.2 and a Cpk of 0.7. What does this indicate? A) The process is centered and capable B) The process is not capable and not centered C) The process is capable but not centered D) The process is centered but not capable Correct Answer: C *Explanation: Cp measures potential capability if centered (1.33+ is typical target). Cpk measures actual capability accounting for centering. Here Cp=1.2 (1) means potential capability exists, but Cpk=0.7 (1) indicates the mean is off-center, causing defects.* ________________________________________ Question 5 Which phase of DMAIC primarily involves hypothesis testing and root cause confirmation? A) Define B) Measure C) Analyze D) Improve Correct Answer: C Explanation: The Analyze phase focuses on identifying and verifying root causes using statistical tools (t-tests, ANOVA, chi-square, regression) and hypothesis testing. Define sets scope, Measure collects baseline data, Improve implements solutions. ________________________________________ Question 6 What does a Pareto chart help prioritize? A) The most frequent causes of defects B) The correlation between two variables C) The stability of a process over time D) The capability of a process Correct Answer: A *Explanation: Based on the 80/20 rule, a Pareto chart ranks categories of defects or causes by frequency/impact, directing improvement efforts to the “vital few” rather than the “trivial many.”* ________________________________________ Question 7 A Six Sigma Black Belt wants to compare the mean cycle time before and after an improvement. The same process is measured on the same days. Which test is appropriate? A) Two-sample t-test B) Paired t-test C) One-way ANOVA D) Chi-square test Correct Answer: B Explanation: Paired t-test is used when observations are naturally paired (e.g., before-after measurements on the same unit or same day), reducing variability due to differences between samples. Two-sample t-test assumes independent groups. ________________________________________ Question 8 Which of the following is a common tool for mistake-proofing? A) 5S B) Poka-Yoke C) Kaizen Blitz D) SIPOC Correct Answer: B *Explanation: Poka-Yoke (Japanese for “mistake-proofing”) designs mechanisms to prevent errors or detect them immediately, such as sensors, guides, or checklists. 5S organizes workspace, Kaizen Blitz is rapid improvement, SIPOC maps high-level process.* ________________________________________ Question 9 In the Measure phase, which metric is defined as (Total opportunities – Total defects) / Total opportunities? A) Sigma level B) Defects per unit (DPU) C) Rolled throughput yield D) First time yield Correct Answer: D Explanation: First time yield (FTY) = units that pass without rework / total units started. Formula given is for FTY. Rolled throughput yield multiplies FTY across steps. DPU = defects/units.