Certified Six Sigma Black Belt Exam Assessment 2

Question 1

A Gauge R&R study reveals that %Study Variation for repeatability is 28% and for reproducibility is 19%. What is the overall assessment of this measurement system?

Accepted Answer

Marginal — total variation exceeds 30% and requires investigation

Answer

When combined %Study Variation (repeatability + reproducibility) exceeds 30%, the measurement system is considered marginal to unacceptable and warrants improvement.

Question 2

Which metric best quantifies the ability of a process to meet customer specifications over the long term, accounting for process shifts?

Accepted Answer

Ppk

Answer

Ppk uses overall (long-term) standard deviation and accounts for process centering, making it the best long-term capability index.

Question 3

During an assessment of a transactional process, a team finds a defect rate of 3,400 DPMO. What sigma level does this correspond to?

Accepted Answer

4.0 sigma

Answer

A DPMO of 3,400 corresponds to approximately 4.0 sigma (short-term), accounting for the standard 1.5 sigma shift.

Question 4

A Black Belt is assessing process stability before calculating capability indices. Which tool is most appropriate for this evaluation?

Accepted Answer

Control chart

Answer

Control charts reveal whether a process is in statistical control (stable) over time, which is a prerequisite for valid capability calculations.

Question 5

In a process assessment, the number of defects per unit (DPU) is 0.08. Assuming a Poisson distribution, what is the approximate first-pass yield (FPY)?

Accepted Answer

92.3%

Answer

FPY = e^(−DPU) = e^(−0.08) ≈ 0.923, or approximately 92.3%.

Certified Six Sigma Black Belt Exam Practice Test

Certified Six Sigma Black Belt Exam Practice Test

Certified Six Sigma Black Belt Exam Assessment 2