Lean Six Sigma Green Belt Certification Prep 5

Question 1

What is the purpose of a 'Poka-Yoke' device in Lean Six Sigma?

Accepted Answer

To mistake-proof a process and prevent defects from occurring or escaping

Answer

Poka-Yoke (Japanese for 'mistake-proofing') devices are designed to prevent errors from occurring or to detect them immediately so they cannot reach the next step.

Question 2

A team is comparing average delivery times between three different shipping carriers. Which statistical test is most appropriate?

Accepted Answer

One-way ANOVA

Answer

One-way ANOVA is used to compare means across three or more groups simultaneously while controlling the risk of Type I error inflation.

Question 3

In a Value Stream Map (VSM), what does a 'push' arrow indicate?

Accepted Answer

Material is pushed to the next step based on a schedule or forecast regardless of need

Answer

A push arrow in VSM indicates that material is moved forward based on production schedules or forecasts, not actual downstream demand — a common source of overproduction waste.

Question 4

What does 'Sigma shift' of 1.5 account for in Six Sigma calculations?

Accepted Answer

Long-term process drift and shift that occurs over time

Answer

The 1.5 sigma shift acknowledges that real processes drift over time, so short-term capability is adjusted to predict long-term performance (e.g., a 6-sigma short-term process yields 3.4 DPMO long-term).

Question 5

Which tool is most appropriate for identifying potential failure modes and their effects before a process is launched?

Accepted Answer

FMEA (Failure Mode and Effects Analysis)

Answer

FMEA proactively identifies potential failures, their effects, and their causes, then prioritizes them by Risk Priority Number (RPN) to focus prevention efforts.

Lean Six Sigma Green Belt Certification Practice Test

Lean Six Sigma Green Belt Certification Practice Test

Lean Six Sigma Green Belt Certification Prep 5