Free Lean Six Sigma Green Belt Practice Test 2026

Question 1Define

A health insurer's claims team reviewed 400 claim forms last week and logged 60 errors across them. Some forms had more than one error. What is the defects per unit (DPU)?

Correct answer: C. 0.15
DPU is total defects divided by total units: 60 / 400 = 0.15. The value 0.85 is one minus DPU, which is not a yield measure when units can carry several defects.

Question 2Measure

A bottling plant runs two 8-hour shifts per day, and each shift includes a 30-minute break. Daily customer demand is 1,200 cases. What is the takt time?

Correct answer: B. 45 seconds
Available time is 2 x (480 - 30) = 900 minutes, or 54,000 seconds. Takt time = 54,000 / 1,200 = 45 seconds per case. The 48 second answer forgets to subtract the breaks.

Question 3Analyze

A food plant team wants to list every possible reason why cookies come out burnt, grouped into categories such as methods, machines, materials and people. Which tool is BEST?

Correct answer: D. A cause and effect diagram
A cause and effect, or fishbone, diagram organizes brainstormed potential causes into categories for a single effect. A Pareto chart ranks causes by frequency only after data on them exists.

Question 4Improve

During a brainstorming session on reducing invoice errors, a senior manager keeps pointing out why each new idea will not work. Which brainstorming rule is being broken?

Correct answer: A. Defer judgment until generation ends
Effective brainstorming separates idea generation from evaluation, so criticism is held until later. Quantity, not quality, is the aim during generation, which makes the third option a common misconception.

Question 5Control

A specialty chemical plant makes one batch per day and records a single purity measurement for each batch. Which control chart is MOST appropriate?

Correct answer: B. I-MR chart
An individuals and moving range (I-MR) chart is used when data come one value at a time, with a subgroup size of one. An Xbar-R chart needs subgroups of several measurements taken together.

Question 6Analyze

A help desk team uses the 5 whys to explain a missed ticket deadline. In which situation is this technique MOST suitable?

Correct answer: A. A fairly simple problem with one likely chain of causes
The 5 whys works best for relatively simple problems where asking why repeatedly can trace a single chain to a root cause. Problems with many interacting factors need data-based tools such as regression or designed experiments.

Question 7Measure

An insurance team suspects that delays come from claims bouncing between underwriting, legal and customer service. Which mapping tool BEST shows who performs each step and where the handoffs occur?

Correct answer: D. A swim lane map
A swim lane map places each step in a lane for the person or department doing it, so handoffs between groups become visible. A SIPOC is too high-level to show individual handoffs.

Question 8Improve

A team plots 12 candidate solutions on an impact/effort matrix. Which group should they generally implement FIRST?

Correct answer: A. High impact, low effort
High impact, low effort ideas are quick wins that deliver results fast at low cost. High impact, high effort ideas may still be worth doing, but they need more planning and resources.

Question 9Define

A contract manufacturer defines 5 defect opportunities on each circuit board. Inspectors check 2,000 boards and find 30 defects in total. What is the DPMO?

Correct answer: C. 3,000
DPMO = defects / (units x opportunities) x 1,000,000 = 30 / (2,000 x 5) x 1,000,000 = 3,000. The figure 15,000 comes from ignoring the 5 opportunities per board.

Question 10Control

A mail center inspects a different number of parcels each day and records how many are mislabeled. Which control chart BEST tracks the fraction mislabeled?

Correct answer: A. p chart
A p chart tracks the proportion of defective units and handles sample sizes that change from day to day. A c chart counts defects in a constant area of opportunity, not the fraction of defective units.

Question 11Measure

Compared with a basic process flowchart, what does a value stream map typically add?

Correct answer: D. Information flow plus a timeline of lead time and value-added time
A value stream map shows material and information flow along with data boxes and a timeline comparing total lead time with value-added time. Control limits belong on control charts, not value stream maps.

Question 12Analyze

A Pareto analysis of 300 shipping errors shows these counts: wrong address 120, wrong item 80, damaged box 50, late label 30, other 20. What percentage of errors do the top two categories account for?

Correct answer: B. 66.7%
The top two categories total 120 + 80 = 200, and 200 / 300 = 66.7%. The 40.0% figure counts only the largest category.

Question 13Define

A loan process has three sequential steps with first pass yields of 95%, 90% and 98%. What is the rolled throughput yield of the whole process?

Correct answer: C. 83.8%
Rolled throughput yield multiplies the step yields: 0.95 x 0.90 x 0.98 = 0.838, or about 83.8%. Averaging the three yields gives 94.3%, which overstates the chance a unit passes every step without rework.

Question 14Improve

A design team compares four new concepts for a checkout process against the current process using + , - and S ratings on each criterion. Which tool are they using?

Correct answer: B. A Pugh matrix
A Pugh matrix compares alternative concepts against a baseline, or datum, rating each as better, worse or the same on each criterion. An FMEA rates risks of failure, not concepts against a baseline.

Question 15Control

A glass maker counts the number of bubbles found on each window pane, and all panes are the same size. Which control chart is MOST appropriate?

Correct answer: D. c chart
A c chart tracks the count of defects per unit when the area of opportunity is constant. A p chart or np chart tracks defective units, which treats a pane with five bubbles the same as a pane with one.

Question 16Measure

A call center collects several metrics. Which one is continuous data?

Correct answer: B. Time to answer a call in seconds
Continuous data can take any value on a scale and can be divided further, such as time. Counts of dropped calls are discrete because they can only be whole numbers.

Question 17Analyze

A ceramics plant wants to see whether kiln temperature is related to the crack rate in finished tiles, using paired readings from 40 batches. Which graph is BEST?

Correct answer: C. A scatter plot
A scatter plot shows the relationship between two continuous variables measured in pairs. A histogram shows the distribution of only one variable.

Question 18Define

A commercial bakery throws away whole batches of bread that fail an in-house taste test before anything leaves the plant. In a cost of poor quality analysis, where does this cost belong?

Correct answer: A. Internal failure cost
Scrap and rework found before the product reaches the customer are internal failure costs. They would be external failure costs only if the bad bread reached customers and caused returns or complaints.

Question 19Improve

A team plans a full factorial experiment with three factors at two levels each, and they will run each combination twice. How many experimental runs are needed?

Correct answer: D. 16
A full factorial with three factors at two levels has 2 x 2 x 2 = 8 combinations. Running each combination twice gives 8 x 2 = 16 runs.

Question 20Control

On a control chart for call handling time, a single point falls above the upper control limit. What should the process owner do?

Correct answer: A. Investigate for a special cause
A point beyond a control limit is a strong signal of special cause variation and should be investigated using the reaction plan. Widening the limits would hide the signal rather than address it.

Question 21Measure

A hospital lab processes samples on three shifts, and the night shift handles only 15% of the volume. The team wants a sample that represents each shift in proportion to its volume. Which sampling method is BEST?

Correct answer: C. Stratified sampling
Stratified sampling divides the population into groups, here shifts, and samples from each group, often in proportion to its size. Simple random sampling could by chance under-represent the small night shift.

Question 22Analyze

A study finds a correlation coefficient of r = -0.85 between hours of operator training and assembly errors. How is this BEST interpreted?

Correct answer: D. A strong negative linear relationship
An r near -1 shows a strong negative linear relationship, so more training goes with fewer errors. The sign shows direction and the size shows strength, so -0.85 is strong, not weak.

Question 23Define

A Green Belt at a logistics firm cannot get shipment data because another department's manager refuses to release it. The project is now two weeks behind. Who is BEST placed to resolve this?

Correct answer: D. The project Champion
The Champion sponsors the project, removes organizational barriers and secures resources across departments. A Master Black Belt coaches on method but usually lacks the line authority to force another department to cooperate.

Question 24Improve

In a two-level experiment, the yields at high temperature were 80 and 84, and the yields at low temperature were 72 and 76. What is the main effect of temperature?

Correct answer: B. 8
The average at high temperature is (80 + 84) / 2 = 82 and at low temperature is (72 + 76) / 2 = 74. The main effect is 82 - 74 = 8. The value 82 is only the high-level average.

Question 25Control

A control chart shows nine consecutive points above the center line, all within the control limits. How should this be interpreted?

Correct answer: C. The process mean has likely shifted, signaling a special cause
A long run of points on one side of the center line, such as nine in a row, is a common rule for detecting a process shift. Points do not need to fall outside the limits to signal a special cause.

Question 26Measure

A team records seven order handling times in minutes: 12, 15, 9, 40, 14, 11, 13. What is the median?

Correct answer: D. 13 minutes
Sorted, the data are 9, 11, 12, 13, 14, 15, 40, and the middle (fourth) value is 13. The mean is 114 / 7 = 16.3, which is pulled upward by the outlier of 40.

Question 27Analyze

At a call center, months with more overtime hours also show higher error rates. A manager says overtime clearly causes the errors. What is the BEST response?

Correct answer: C. Note that correlation alone does not prove cause
Correlation shows that two variables move together, but a third factor, such as seasonal call volume, could drive both. The team should verify the causal link with further analysis or an experiment before acting.

Question 28Define

Which of the following is the BEST problem statement for a Six Sigma project charter?

Correct answer: B. From April to June, 14% of Dallas orders shipped late versus a 3% target.
A good problem statement describes what, where, when and how big, with data, and avoids naming causes or solutions. The first option assumes a root cause and blames people before any analysis has been done.

Question 29Improve

In a designed experiment, raising pressure improves seal strength at low temperature but weakens it at high temperature. What does this show?

Correct answer: C. An interaction of pressure and temperature
An interaction exists when the effect of one factor depends on the level of another factor. A main effect alone would show pressure acting the same way at every temperature.

Question 30Control

A process is in statistical control, yet about 4% of its output falls outside the customer's specification limits. What does this mean?

Correct answer: A. The process is stable but not capable
Control limits describe what the process does, while specification limits describe what the customer needs. A stable process can still be incapable, and fixing it requires reducing common cause variation or re-centering.

Question 31Measure

A technician measures three parts and gets 4, 6 and 8 millimeters. What is the sample standard deviation?

Correct answer: B. 2.00 mm
The mean is 6, the squared deviations are 4, 0 and 4, and their sum of 8 divided by n - 1 = 2 gives a variance of 4. The square root is 2.00 mm. Dividing by n = 3 instead gives 1.63, which is the population formula.

Question 32Analyze

A regression model for delivery time is Y = 12 + 3.5X, where X is the number of stops and Y is minutes. What is the predicted delivery time for 8 stops?

Correct answer: A. 40 minutes
Substitute X = 8: Y = 12 + 3.5 x 8 = 12 + 28 = 40 minutes. The 28 minute answer leaves out the intercept of 12.

Question 33Define

A hospital team's current average discharge time is 5.5 hours after the doctor's order. Which goal statement is BEST written?

Correct answer: C. Reduce average discharge time from 5.5 to 3 hours by June 30
A goal statement should be specific, measurable and time-bound, stating the baseline, target and deadline. The option about a tracking board names a solution instead of the result to be achieved.

Question 34Improve

Why does a team randomize the run order in a designed experiment?

Correct answer: D. To guard against hidden time effects
Randomizing the run order spreads the influence of uncontrolled factors, such as tool wear or ambient temperature, across all runs. It does not reduce the number of runs or guarantee significant results.

Question 35Control

An I-MR chart has an average of 50.0 and an average moving range of 2.0. Using the constant 2.66, what is the upper control limit for the individuals chart?

Correct answer: D. 55.32
The individuals chart UCL = mean + 2.66 x average moving range = 50.0 + 2.66 x 2.0 = 50.0 + 5.32 = 55.32. The 52.66 answer adds the constant itself instead of multiplying it by the moving range.

Question 36Measure

A histogram of fill weights from a packaging line shows two distinct peaks. What is the MOST likely explanation?

Correct answer: A. The data come from two different sources mixed together
A bimodal histogram usually means two populations are mixed, such as two machines, shifts or material lots. The team should stratify the data by likely source to separate them.

Question 37Analyze

A simple linear regression of energy use against production volume has an R-squared of 0.72. What does this mean?

Correct answer: B. Volume explains 72% of the variation in energy use
R-squared is the proportion of variation in the response explained by the model. It does not prove causation, and the correlation coefficient would be the square root, about 0.85.

Question 38Define

At the first meeting of a procurement project, team members argue about where the purchasing process starts and ends and who feeds it. What tool should the Green Belt use FIRST?

Correct answer: D. A SIPOC diagram
A SIPOC gives a high-level view of suppliers, inputs, process steps, outputs and customers, which sets the process boundaries early in Define. A detailed swim lane map comes later and is hard to build before the boundaries are agreed.

Question 39Improve

A Green Belt has chosen a new scheduling method for a clinic chain with 30 sites. What is the MAIN reason to pilot it at one site first?

Correct answer: C. To test it small and catch problems early
A pilot tests the solution under real conditions on a small scale, confirms the expected results and uncovers unintended problems before a full rollout. It reduces risk, rather than delaying or replacing later phases.

Question 40Control

A technician sets up a new Xbar-R chart. Why should the R chart be reviewed BEFORE the Xbar chart?

Correct answer: B. The Xbar limits are based on the average range
The Xbar chart's control limits are calculated from the average range, so if the range chart is out of control, the Xbar limits are not reliable. The R chart says nothing about meeting specifications.

Question 41Measure

On a box plot of delivery times, what does the box itself represent?

Correct answer: C. The middle 50% of the data
The box spans the first quartile to the third quartile, which is the interquartile range covering the middle 50% of the data. The whiskers, not the box, extend toward the minimum and maximum.

Question 42Analyze

A team wants to test whether two suppliers' bolts have different mean tensile strengths. What is the null hypothesis?

Correct answer: A. The two suppliers have equal means
The null hypothesis states no difference or no effect, so here the two means are equal. The statement that the means differ is the alternative hypothesis the team is looking for evidence to support.

Question 43Define

A bank's customers say, "I want to hear back on my loan quickly." Which is the BEST critical to quality (CTQ) requirement derived from this voice of the customer?

Correct answer: B. Decision sent within 48 hours of a complete application
A CTQ turns a vague customer need into a measurable requirement with a clear target. The option about feeling the process is fast restates the need but cannot be measured against a limit.

Question 44Improve

Which description BEST fits a kaizen event?

Correct answer: A. A cross-functional team improving one area in days
A kaizen event is a short, intensive improvement effort, often three to five days, where a cross-functional team analyzes and changes a specific process. It emphasizes quick action rather than long studies.

Question 45Control

A Green Belt is drafting a control plan for a new packing process. Which content is MOST essential?

Correct answer: C. The measure, method, frequency, owner and reaction
A control plan lists what is measured, how and how often, who is responsible and what to do when results go out of control. Brainstorming history and team ratings do not help the process owner run the process.

Question 46Measure

Inspectors at a garment plant need a quick, structured way to tally defect types by hour as they occur on the line. Which tool is BEST?

Correct answer: B. A check sheet
A check sheet is a simple form for recording counts or events in real time, organized by category and time. A scatter plot shows the relationship between two variables, not tallies of defect types.

Question 47Analyze

A 2-sample t-test comparing two packaging methods gives a p-value of 0.02. The team set alpha at 0.05. What should they conclude?

Correct answer: D. Reject the null; the means differ
When the p-value is below alpha, the null hypothesis is rejected, so the difference is statistically significant. Failing to reject would apply only if the p-value were above 0.05.

Question 48Define

A finance group spends four hours each week adding colored charts and extra tabs to a report that managers only use for one total figure. Which of the eight wastes is this?

Correct answer: A. Overprocessing
Overprocessing is doing more work or adding more features than the customer values. Overproduction means making more output or making it sooner than needed, which is a different problem from adding unneeded detail.

Question 49Improve

During a setup reduction effort, a team starts preheating the next mold while the press is still running the current job. What does this change achieve in SMED terms?

Correct answer: B. It converts internal setup work to external
Internal setup can only be done when the machine is stopped, while external setup can be done while it runs. Preheating during production moves work from internal to external, shortening downtime.

Question 50Control

A control chart operator sees a signal on the night shift. What document should tell her exactly which steps to take, including containing suspect product?

Correct answer: D. The reaction plan
The reaction, or response, plan in the control plan spells out immediate actions when a signal occurs, such as stopping, containing product and escalating. The project charter defines the project, not daily responses.

Question 51Measure

Package weights are normally distributed with a mean of 50 grams and a standard deviation of 5 grams. About what percentage of packages weigh between 40 and 60 grams?

Correct answer: D. 95%
40 and 60 grams are two standard deviations below and above the mean, and about 95% of a normal distribution falls within plus or minus 2 sigma. 68% would apply to the range 45 to 55 grams.

Question 52Analyze

A team concludes that a new resin improves part strength, and the plant switches suppliers. Later studies show the new resin made no real difference. Which error did the team make?

Correct answer: A. A Type I error
A Type I error is rejecting a true null hypothesis, concluding there is a difference when there is none. A Type II error is the opposite: missing a difference that really exists.

Question 53Define

Nurses on a surgical ward walk to a supply room at the far end of the corridor several times per shift to fetch gauze and gloves. Which waste does this walking represent?

Correct answer: C. Motion
Motion is unnecessary movement of people, such as walking, reaching or searching. Transportation refers to moving materials or products between locations, not the movement of workers.

Question 54Improve

In a hospital supply room, an empty bin with a card triggers a reorder of exactly one bin of supplies. Which Lean tool is this?

Correct answer: A. Kanban
A kanban is a visual signal that authorizes replenishment of only what has been used. Poka-yoke is mistake-proofing, which is a different purpose.

Question 55Control

A machine shop paints the outline of each tool on a pegboard so anyone can see at a glance when a tool is missing. What kind of control is this?

Correct answer: B. A visual control
A shadow board is a visual control that makes the normal state obvious and abnormal conditions easy to spot. It is a common way to sustain 5S and standard work.

Question 56Measure

In a gage study, one operator measures the same part ten times with the same caliper and gets noticeably different readings. Which source of measurement variation does this show?

Correct answer: B. Repeatability
Repeatability, also called equipment variation, is the variation when the same person measures the same part repeatedly with the same device. Reproducibility is the variation between different operators.

Question 57Analyze

Before running any formal test, a Green Belt wants to visually compare the center, spread and outliers of cycle times across three shifts on one graph. Which graph is BEST?

Correct answer: C. Side-by-side box plots
Side-by-side box plots show the median, spread and outliers of each group at a glance, making group differences easy to see. A single histogram of all the data mixes the shifts together and hides the comparison.

Question 58Define

A maintenance shop is starting a 5S program. Benches are crowded with broken tools, old parts and items nobody has used in a year. Which step should come FIRST?

Correct answer: B. Sort
Sort comes first: remove items that are not needed so only necessary tools remain. Set in order is the second step, and organizing clutter before removing it wastes effort.

Question 59Improve

A connector on a medical device is shaped so it can only be plugged in one way, making a wrong connection impossible. What kind of tool is this?

Correct answer: D. A prevention-type poka-yoke
A prevention-type poka-yoke makes the error physically impossible, which is the strongest form of mistake-proofing. Visual controls make the right action clear but do not stop the wrong one.

Question 60Control

A team has proven a new method for loading trucks. What should happen to the standard operating procedure before the project closes?

Correct answer: A. Update the SOP and train staff on it
The SOP must reflect the new method, and people must be trained on it, or the process will drift back to old habits. Relying on team memory fails as soon as staff change.

Question 61Measure

A gage R&R study on a torque tester shows that measurement variation is 35% of the total study variation. What should the team do NEXT?

Correct answer: C. Improve the measurement system first
A gage R&R above 30% is generally considered unacceptable, so the measurement system must be fixed before baseline data can be trusted. Under 10% is generally acceptable, and 10% to 30% may be acceptable depending on the application.

Question 62Analyze

A plant wants to know whether the mean fill weight differs among its four filling machines. Which test is MOST appropriate?

Correct answer: A. One-way ANOVA
One-way ANOVA compares the means of three or more groups in a single test. Running many 2-sample t-tests would increase the overall chance of a Type I error.

Question 63Define

In a custom furniture shop, which activity is MOST likely value-added from the customer's point of view?

Correct answer: D. Staining and sealing the tabletop
Value-added work changes the form or function of the product in a way the customer will pay for, and is done right the first time. Inspection may be required, but it does not change the product.

Question 64Improve

A Green Belt is writing standard work for an assembly cell. Which three elements are MOST commonly included?

Correct answer: A. Takt time, work sequence and standard WIP
Standard work is usually built on takt time, the sequence of work steps and the standard amount of work in process. The other options are useful tools in other phases but are not the elements of standard work.

Question 65Control

A Green Belt project is ready to close. What is the MOST important step in handing the process back?

Correct answer: C. The process owner accepts the control plan
Sustaining gains depends on the process owner taking ownership of the control plan, monitoring and reaction plans. If the Green Belt keeps monitoring, control stops when that person moves to another project.

Question 66Measure

Three inspectors judge painted panels as pass or fail by eye. The team wants to know whether inspectors agree with each other and with an expert standard. Which study is MOST appropriate?

Correct answer: D. An attribute agreement analysis
Attribute agreement analysis assesses pass or fail and other categorical judgments for agreement within and between appraisers and against a standard. A variable gage R&R needs continuous measurements.

Question 67Analyze

A team wants to know whether the type of defect (scratch, dent or stain) depends on which shift produced the part. Both variables are categories. Which test is MOST appropriate?

Correct answer: D. Chi-square test of independence
A chi-square test of independence checks whether two categorical variables are related, using counts in a table. ANOVA needs a continuous response, which the defect type is not.

Question 68Define

A permit application spends a total lead time of 15 hours in a city office, but only 45 minutes of that time is spent actually working on it. What is the process cycle efficiency?

Correct answer: B. 5%
Process cycle efficiency is value-added time divided by total lead time: 45 minutes / 900 minutes = 0.05, or 5%. A result of 20% comes from dividing 15 by 45 minutes in mixed units, which is not valid.

Question 69Improve

A batch of 10 units moves through three steps, and each step takes 1 minute per unit. If the team switches to one-piece flow, when will the last unit be finished?

Correct answer: C. 12 minutes
With one-piece flow, the first unit finishes after 3 minutes, and each later unit finishes 1 minute after the previous one, so the last unit is done at 3 + 9 = 12 minutes. Moving the whole batch together would take 30 minutes.

Question 70Control

A team wants the MOST reliable way to prevent operators from skipping a critical torque step. Which control is strongest?

Correct answer: B. A fixture that blocks release until torque is met
Mistake-proofing that physically prevents the error is the strongest control because it does not rely on memory or attention. Training, signs and spot checks all depend on people catching the problem.

Question 71Measure

A shaft diameter has an upper specification of 112 mm and a lower specification of 88 mm. The process standard deviation is 2.5 mm. What is Cp?

Correct answer: C. 1.60
Cp = (USL - LSL) / (6 x sigma) = (112 - 88) / (6 x 2.5) = 24 / 15 = 1.60. Using 3 sigma in the denominator would wrongly give 3.20.

Question 72Analyze

A paint line's viscosity has been stable for months. One morning it jumps sharply right after a new lot of solvent is put into use. How is this variation BEST described?

Correct answer: B. Special cause variation
Special cause variation comes from a specific, identifiable event outside the usual system, such as a new material lot. Common cause variation is the steady background noise built into the process.

Question 73Define

Hotel guests rarely mention clean bed sheets in surveys, but they complain strongly when sheets are stained. In the Kano model, clean sheets are BEST described as what type of need?

Correct answer: C. A basic need
Basic or must-be needs are expected; meeting them does not create satisfaction, but missing them causes strong dissatisfaction. A performance need increases satisfaction steadily as it improves, which is not the pattern described.

Question 74Improve

In an FMEA for a new order entry system, one failure mode is rated severity 8, occurrence 4 and detection 6. What is its risk priority number?

Correct answer: A. 192
RPN = severity x occurrence x detection = 8 x 4 x 6 = 192. The value 18 is the sum of the ratings, which is not how RPN is calculated.

Question 75Control

A Green Belt reports $180,000 in annual savings from a project. Before the savings are officially claimed, who should normally validate them?

Correct answer: D. The finance department
Finance validates project savings using agreed accounting rules, which makes the claimed benefits credible. A Green Belt's own estimate may be biased or count savings that never reach the bottom line.

Question 76Measure

A process has a Cp of 1.8 but a Cpk of 0.9. What does this MOST likely indicate?

Correct answer: A. The process is not centered between the limits
Cp compares spread to the specification width, while Cpk also accounts for centering. A high Cp with a much lower Cpk means the spread could fit, but the mean is shifted toward one limit.

Question 77Analyze

An operator adjusts a machine setting after every part, even when readings are well within the control limits. What is the MOST likely effect?

Correct answer: C. Variation will increase
Adjusting a stable process in response to common cause variation is called tampering, and it adds variation rather than removing it. A stable process should be left alone unless a special cause signal appears.

Question 78Define

Halfway through Define, the sponsor of a returns-processing project keeps asking the team to also look at supplier invoicing and warehouse staffing. What should the Green Belt do FIRST?

Correct answer: D. Refer to the charter scope and log extra items
The charter's in-scope and out-of-scope boundaries protect the project from scope creep. Extra topics should be recorded and discussed with the Champion as separate projects, not quietly added to the current one.

Question 79Improve

An FMEA lists a failure mode with an RPN of 90 and a severity of 10, which could injure a customer. Another failure mode has an RPN of 160 and a severity of 4. How should the team treat the first one?

Correct answer: D. Give it high priority despite its lower RPN
Many teams act on any failure mode with a very high severity regardless of RPN, because safety risks should not be outweighed by frequent minor issues. Ranking purely by RPN can hide rare but dangerous failures.

Question 80Control

After a successful improvement, a control chart shows a clear, sustained shift to a better level that the team has confirmed. What should be done with the control limits?

Correct answer: B. Recalculate them using post-change data
Once a process change is confirmed and stable, limits should be recalculated from post-change data so the chart reflects the new process. Keeping old limits would make the chart blind to problems at the new level.

Question 81Measure

Two inspectors at a phone refurbisher disagree on whether a screen has a "scratch," so their defect counts differ widely. What should the team do FIRST?

Correct answer: B. Write a clear operational definition
An operational definition states exactly what counts as a scratch and how to check for it, so everyone measures the same way. Averaging the counts hides the disagreement instead of removing it.

Question 82Analyze

With a sample of 20,000 transactions, a team finds that a new screen layout cuts average entry time by 0.2 seconds, with a p-value of 0.001. What is the BEST interpretation?

Correct answer: D. It is significant, but the gain may be too small
Large samples can make tiny differences statistically significant. The team must also judge practical significance, such as whether 0.2 seconds is worth the cost of the change.

Question 83Define

An auditor checks 50 invoices and finds 12 errors spread across 8 of the invoices. What percentage of invoices are defective?

Correct answer: C. 16%
A defective unit has one or more defects, so 8 defective invoices out of 50 gives 8 / 50 = 16%. The 24% figure counts defects (12 / 50) instead of defective units.

Question 84Improve

A cell has a total work content of 240 seconds per unit, and the takt time is 60 seconds. What is the minimum number of operators needed to meet demand?

Correct answer: B. 4
The minimum number of operators is total work content divided by takt time: 240 / 60 = 4. With fewer than 4, at least one operator would have more than 60 seconds of work per unit.

Question 85Control

A team sets up an Xbar-R chart for a filling line. How should each subgroup BEST be formed?

Correct answer: C. From several consecutive fills taken close together
Rational subgroups are formed so variation within each subgroup reflects only common causes, which usually means consecutive units taken close together. Spreading a subgroup across a week or several lines mixes in special causes.

Question 86Measure

A scale gives readings tightly clustered together, but they are consistently 0.3 kg above the certified reference weight. How is this measurement system BEST described?

Correct answer: A. Precise but biased
Tight clustering means good precision, while a consistent offset from the true value is bias, a lack of accuracy. A calibration adjustment can usually correct this kind of bias.

Question 87Analyze

A frequency Pareto shows minor labeling errors as the most common defect, but a cost Pareto shows rare motor failures cost far more. The project goal is to cut warranty cost. What should the team focus on?

Correct answer: B. Motor failures because they drive the most cost
A Pareto should be weighted by the measure that matches the goal, so a cost goal calls for the cost-weighted chart. Frequency alone can point the team at defects that are common but cheap.

Question 88Define

A Green Belt is told to balance the voice of the customer with the voice of the business. Which item is an example of the voice of the business?

Correct answer: A. A goal to cut cost per order by 10%
The voice of the business reflects the organization's needs, such as cost, profit and efficiency targets. The other options come from customers and represent the voice of the customer.

Question 89Improve

Which statement BEST describes a pull system?

Correct answer: C. Work is triggered by actual downstream use
In a pull system, upstream processes produce only when downstream processes or customers use something. Producing to a forecast schedule is a push system.

Question 90Control

At project closure, the team holds a session to record what went well, what did not and what they would do differently. What is the MAIN purpose?

Correct answer: D. To capture lessons learned for future projects
A lessons learned review captures knowledge so future projects can repeat successes and avoid mistakes. It is not about assigning blame, and it does not replace the control plan.

Question 91Measure

A claims department has an average of 300 claims in process, and it completes about 60 claims per day. Using Little's Law, what is the average lead time?

Correct answer: D. 5 days
Little's Law says lead time = work in process / throughput = 300 / 60 = 5 days. The 0.2 day answer comes from dividing throughput by WIP, which inverts the formula.

Question 92Analyze

A regression model for curing time was built using oven temperatures from 150 to 200 degrees. A manager wants to use it to predict curing time at 260 degrees. What is the BEST advice?

Correct answer: A. Avoid predicting far outside the data range
Predicting beyond the range of the data used to build a model is extrapolation, and the relationship may change outside that range. A high R-squared within the range does not guarantee the model holds at 260 degrees.

Question 93Define

A claims process has very few errors, but each claim spends days waiting in queues between handoffs. Which approach is MOST likely to give the biggest gain first?

Correct answer: B. Lean tools to remove waiting and improve flow
Lean focuses on removing waste and speeding up flow, which fits a process with long queues but low error rates. Six Sigma variation reduction is strongest when defects and inconsistency are the main issue.

Question 94Improve

A new billing process will change daily routines for 40 clerks, and several are openly resistant. What is the BEST way for the Green Belt to reduce resistance?

Correct answer: D. Involve the clerks early in shaping it
People are more likely to support changes they helped shape, so involving affected staff early builds ownership and surfaces practical problems. Forcing the change through discipline often creates hidden resistance.

Question 95Control

An Xbar-R chart uses subgroups of 5. The grand average is 20.0 and the average range is 1.5. With A2 = 0.577, what is the upper control limit for the Xbar chart?

Correct answer: C. 20.87
UCL = grand average + A2 x average range = 20.0 + 0.577 x 1.5 = 20.0 + 0.87 = 20.87. The 21.50 answer adds the average range directly without the A2 constant.

Question 96Measure

A team wants to report Cpk for a molding process to a customer. What should they confirm BEFORE calculating it?

Correct answer: A. That the process is stable and in control
Capability indices only predict future performance when the process is stable, so a control chart should show no special causes first. Having all output within specification today does not make the result predictive.

Question 97Analyze

A team's fishbone diagram lists 25 possible causes of late invoices, and members strongly believe the main cause is a new billing system. What should they do BEFORE moving to Improve?

Correct answer: C. Verify the suspected cause with data
Analyze is about confirming root causes with data, such as stratified analysis or hypothesis tests, before solutions are chosen. Voting reflects opinion and can lead to fixing the wrong cause.

Question 98Define

A new Green Belt at a chemical plant is struggling to choose the right statistical tools for her first project. In a typical deployment, who is her MOST likely day-to-day coach?

Correct answer: A. A Black Belt
Black Belts usually lead larger projects and mentor Green Belts on tools and methods. The Champion sponsors the project and removes barriers but is not normally the technical coach.

Question 99Improve

A weighted selection matrix uses three criteria: cost (weight 3), impact (weight 5) and ease (weight 2). Solution A scores 4, 3 and 5. Solution B scores 2, 5 and 2. Which solution scores higher?

Correct answer: B. Solution A, with 37 points
Solution A scores 4 x 3 + 3 x 5 + 5 x 2 = 12 + 15 + 10 = 37. Solution B scores 2 x 3 + 5 x 5 + 2 x 2 = 6 + 25 + 4 = 35, so A wins. The value 12 is the unweighted sum of A's scores.

Question 100Control

Six months after a project closed, a plant wants to make sure the new standard work is still being followed. What is the BEST approach?

Correct answer: A. Schedule regular audits of the standard work
Regular audits, such as layered process audits by supervisors and managers, check that standards are followed and catch drift early. Waiting for operators to report drift assumes people will notice and speak up.