CQE (CQE) Fundamentals 4 — Questions and Answers
Question 1: Which type of control chart is MOST appropriate for monitoring the proportion of defective items in subgroups of varying size?
- c-chart
- np-chart
- p-chart (Correct answer)
- u-chart
Correct answer: p-chart
The p-chart monitors the proportion (fraction) defective and accommodates varying subgroup sizes, unlike the np-chart which requires constant size.
Question 2: In Failure Mode and Effects Analysis (FMEA), the Risk Priority Number (RPN) is calculated as:
- Severity × Occurrence
- Severity + Occurrence + Detection
- Severity × Occurrence × Detection (Correct answer)
- Occurrence × Detection only
Correct answer: Severity × Occurrence × Detection
RPN = Severity × Occurrence × Detection, and is used to prioritize which failure modes require corrective action.
Question 3: A Type I error in hypothesis testing means:
- Failing to detect a real difference (false negative)
- Rejecting the null hypothesis when it is actually true (false positive) (Correct answer)
- Accepting a bad lot during inspection
- Underestimating process variation
Correct answer: Rejecting the null hypothesis when it is actually true (false positive)
A Type I error (alpha error) occurs when the null hypothesis is rejected even though it is true — a false positive conclusion.
Question 4: Which quality tool is MOST appropriate for analyzing whether a relationship exists between two continuous variables?
- Histogram
- Scatter diagram (Correct answer)
- Control chart
- Affinity diagram
Correct answer: Scatter diagram
A scatter diagram plots pairs of data to visually assess the correlation (relationship) between two continuous variables.
Question 5: The primary difference between Quality Assurance (QA) and Quality Control (QC) is that:
- QA detects defects; QC prevents them
- QA is process-focused and preventive; QC is product-focused and detection-based (Correct answer)
- QC is strategic while QA is tactical
- QA is performed only by management; QC by operators
Correct answer: QA is process-focused and preventive; QC is product-focused and detection-based
QA focuses on processes and preventing defects from occurring, while QC focuses on inspecting products to detect defects.
Question 6: Under ISO 9001:2015, which element is explicitly required to be documented as retained evidence of conformity?
- Corrective action register
- Management review agenda
- Records of monitoring and measurement results (Correct answer)
- Supplier evaluation criteria
Correct answer: Records of monitoring and measurement results
ISO 9001:2015 requires retaining documented information (records) as evidence that monitoring and measurement results conform to requirements.
Question 7: A gage R&R study reveals that measurement system variation accounts for 35% of total observed variation. This result indicates:
- The measurement system is acceptable for production use
- The measurement system may need improvement before making process decisions (Correct answer)
- The gage is perfectly calibrated
- The process has excessive within-part variation
Correct answer: The measurement system may need improvement before making process decisions
AIAG guidelines classify a gage R&R above 30% as unacceptable, requiring corrective action before the gage is used for process decisions.
CQE (CQE) Fundamentals 4
Which type of control chart is MOST appropriate for monitoring the proportion of defective items in subgroups of varying size?