Lean Six Sigma Black Belt Certification Prep 1

Question 1

In Measurement System Analysis (MSA), a %GR&R value greater than 30% indicates what about the measurement system?

Accepted Answer

The system is unacceptable and must be improved before use

Answer

Per AIAG MSA guidelines, %GR&R below 10% is acceptable, 10–30% may be acceptable based on the application, and above 30% means the measurement system is unacceptable — gauge variation is too large relative to total variation, making it unreliable for distinguishing good parts from bad.

Question 2

Which control chart should be used to monitor the number of defects per unit when subgroup sizes vary from sample to sample?

Accepted Answer

u-chart

Answer

The u-chart tracks defects per unit and accommodates variable subgroup sizes, making it the correct choice when sample sizes change. The c-chart also counts defects but requires constant subgroup size. The p-chart and np-chart track the proportion or count of defective units, not defects.

Question 3

A full factorial Design of Experiment (DOE) with 4 factors each set at 2 levels requires how many experimental runs without replication?

Accepted Answer

16

Answer

A 2^k full factorial design requires 2^k runs. With k = 4 factors, that is 2^4 = 16 runs. This design allows estimation of all main effects and all two-, three-, and four-way interaction effects without any confounding.

Question 4

A process yields Cp = 1.60 and Cpk = 0.75. What is the most accurate interpretation?

Accepted Answer

The process spread is sufficient but the mean is significantly shifted off-center

Answer

Cp measures potential capability based on spread alone without regard to centering. Cpk adjusts for how far the mean has drifted from the target. A high Cp with a low Cpk means the process distribution is narrow enough to fit within spec limits, but it is off-center, producing defects on one tail.

Question 5

On a Value Stream Map (VSM), what does a kaizen burst symbol represent?

Accepted Answer

A location targeted for focused rapid improvement activity

Answer

The kaizen burst (starburst or lightning-bolt shape) is placed on a VSM to highlight areas where waste or problems have been identified and where a rapid improvement event — a kaizen workshop — should be conducted. It is an action flag, not a data symbol.

Lean Six Sigma Black Belt Certification Practice Test

Lean Six Sigma Black Belt Certification Practice Test

Lean Six Sigma Black Belt Certification Prep 1