Lean Six Sigma Green Belt Certification Lean Principles and Waste 5 — Questions and Answers
Question 1: Which Lean concept refers to leveling the production schedule to smooth out volume and mix variations over time?
- Poka-yoke
- Heijunka (Correct answer)
- Jidoka
- Andon
Correct answer: Heijunka
Heijunka is the Lean practice of production leveling — distributing work evenly over time to avoid peaks and valleys that create waste and stress.
Question 2: When a Green Belt calculates process efficiency on a value stream map, what ratio is being computed?
- Total lead time divided by takt time
- Value-added time divided by total lead time (Correct answer)
- Cycle time divided by available production time
- Throughput divided by work-in-process
Correct answer: Value-added time divided by total lead time
Process efficiency (or process cycle efficiency) is the ratio of value-added time to total lead time, often expressed as a percentage to highlight waste.
Question 3: A service team discovers they are entering the same customer data into three separate systems. Which waste type does this represent?
- Defects
- Transportation
- Over-processing (Correct answer)
- Motion
Correct answer: Over-processing
Redundant data entry across multiple systems is over-processing waste — performing more steps than necessary to deliver the required output.
Question 4: Which of the following Lean principles must be established before a pull system can function effectively?
- Seek perfection
- Define value
- Create flow (Correct answer)
- Map the value stream
Correct answer: Create flow
Flow must be established before pull can work — without continuous, uninterrupted flow, downstream signals cannot reliably pace upstream production.
Question 5: In a transactional process, which of the following is MOST likely classified as waiting waste?
- Sending an email confirmation to a customer
- A loan application sitting in a queue for 3 days awaiting underwriter review (Correct answer)
- Archiving completed transactions
- Running an automated report at end of day
Correct answer: A loan application sitting in a queue for 3 days awaiting underwriter review
A loan application sitting idle while awaiting review is classic waiting waste — work that is complete on one end but cannot proceed because a resource is unavailable.
Question 6: Which statement BEST distinguishes 'muda' from 'mura' in Lean terminology?
- Muda is overburden; mura is waste
- Muda is waste; mura is unevenness or variation in workflow (Correct answer)
- Muda is continuous improvement; mura is error-proofing
- Muda is takt time; mura is cycle time
Correct answer: Muda is waste; mura is unevenness or variation in workflow
Muda means waste (non-value-added activity), while mura refers to unevenness or irregularity in the flow of work, both of which Lean seeks to eliminate.
Question 7: A team implements standard work instructions to ensure every operator performs a task the same way. Which Lean goal does this PRIMARILY support?
- Increasing inventory buffers
- Reducing variation and establishing a baseline for continuous improvement (Correct answer)
- Maximizing machine utilization
- Eliminating the need for skilled operators
Correct answer: Reducing variation and establishing a baseline for continuous improvement
Standard work reduces process variation and creates a documented baseline from which kaizen improvements can be measured and sustained.
Lean Six Sigma Green Belt Certification Lean Principles and Waste 5
Which Lean concept refers to leveling the production schedule to smooth out volume and mix variations over time?