Black Belt Exam WARNING!!!!! If you refresh your browser or close this page before completing the exam, your answers will not be saved! 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051 Black Belt Exam Black Belt exam for students using Excel add-ins SuperEasyStats and DOEPro 1 / 51 Your name (you will not get credit for your answers if you don't enter your name!) Check 2 / 51 A company is trying to optimize their product manufacturing process, so they conduct a VSM. They find that the Inspection station seems to be a bottleneck. They sample the Inspection station’s cycle times each day for a week. Using the chart and the data, select the closest estimate of the Operational Equipment Effectiveness (OEE) for the Inspection Station. (click here for larger image) 97% 99% 69% 72% 3 / 51 If an Inspection Station has a historical reject rate of 5%, what is the chance they will see 5 rejects out of 100 units inspected? 5% 100% 72% 18% 4 / 51 If an Inspection Station has a historical reject rate of 7.5%, what is the chance they will see just 1 reject out of 60 units inspected? 5.45% 99% 4.52% 0.93% 5 / 51 The average time for a student to complete the Green Belt exam is 3 hours and 20 minutes with a standard deviation of 20 minutes. The times are normally distributed. Among a recent group of test takers, one student completed the exam in 1 hour and 30 minutes, and another took 4 hours and 10 minutes. What is the probability that a student will take less than 1 hour and 30 minutes or more than or 4 hours and 10 minutes to complete the exam? 99.38% 5.31% 0.62% 11.72% 6 / 51 The Accounts Receivable department tracks how long it takes to receive payment from their largest client. The average time is 35 days with a standard deviation of 5 days. The times are normally distributed. What is the probability of receiving a payment within 25 - 28 days? 6.3% 94.92% 5.8% 2.275% 7 / 51 A manufacturing line experiences stops whenever incoming raw material supply falls below a specified level. The stops last an average of 11.5 minutes with a standard deviation of 4.26 minutes. The times are normally distributed. What is the time above which the longest 5% of stops last? 13.08 minutes 18.51 minutes 15.76 minutes 8.75 minutes 8 / 51 A training organization has all new employees take an exam after attending a series of classes intended to teach them how to use the internal document control system. The average score on the exam is 81% with a standard deviation of 6.7%. The scores are normally distributed. What is the score below which the bottom 5% of results fall? 60.9 58.3 65.4 69.9 9 / 51 A regional airport determines that during peak hours (9am - 4pm Tuesday through Friday), on average they manage an incoming flight every 5 minutes. What is the probability of a flight arriving within 2 minutes of the previous flight? 47.3% 32.9% 17.6% 67.03% 10 / 51 A customer support line determines that customers wait an average of 7.75 minutes before getting connected to a support representative. What is the probability of a customer getting connected within 3 - 4 minutes? 8.2% 21.4% 13.8% 10.5% 11 / 51 A factory tracks accidents and finds that they experience and average of 2 accidents per month. What is the probability that they will suffer 5 or more accidents in a single month? 1.6% 18.4% 98.3% 5.3% 12 / 51 A company sets up kaizen system to allow employees to submit improvement ideas. Over the past year the the system has received an average of 12 suggestions per week. Recently the number of suggestions has jumped to between 16 and 18. If the average number of submissions really is 12 per week, what is the probability of receiving between 16 and 18 submissions in a single week? 88.2% 11.8% 96.2% 3.8% 13 / 51 Select the 8 classic categories of waste in Lean thinking. Underproduction Time Waste Transportation Oversimplification Mistakes Underutilization/Skills Overproduction Defects Waiting Overcommitment Urgency Motion Overprocessing Inventory Inefficiency 14 / 51 The amount of time someone spends actually working on a task, not including interruptions is called: Process time Lead time Changeover time 15 / 51 The total amount of time required to complete a process step, including interruptions and other delays is called: Lead time Changeover time Process time 16 / 51 The amount of time that elapses when a machine is stopped on purpose to set it up for a different task is called: Process time Changeover time Lead time 17 / 51 The calculation for takt time is which of the following? Time available / Cycle time * Available employees Time available / Customer demand Cycle time / Time available Customer demand / cycle time 18 / 51 Kanban is a system that allows us to control... Defects Inventory Overprocessing Time 19 / 51 Which of the following indicate opportunities for improvement on a current state value stream map? (select all that apply) Short cycle times Large discrepancies between process time and lead time Long wait times between steps Process steps that are operating more slowly than the step before them Steps with %Complete and Accurate (%C/A) below 100% 20 / 51 Based on the information shown here, what waste do we know will result from these two steps in a VSM? (click here for larger image) Excess transportation of subassemblies from the supplier Inventory piling up between the two steps Too much operator motion in the second step Overprocessing of parts in the first step 21 / 51 When building our future state VSM, we must look at the current state and determine if the steps are: Value-add, useful and cost-effective Value-add but not required, time-efficient or defective Value-add, non-value-add, or non-value-add but required Legal, compliant, or non-value-add but required 22 / 51 When conducting a current state VSM, it is recommended that you have the team do what before starting the mapping session? Avoid sharing information so other members of the team don't become biased Walk the gemba Propose solutions Speculate on possible causes 23 / 51 When conducting a 5-why analysis, it is important to check our work by starting at answer to the final "why", and work backwards by saying... "therefore..." "why not?" "who?" "but not..." 24 / 51 When building a fishbone diagram, common categories for the "bones" are (select all that apply): Problems Methods Reasons Documents Kanban Mother Nature (environment) Machines People Waste Measurement Mistakes Materials 25 / 51 A company has newly hired sales associates watch a series of five training videos that are each one hour long before starting in their new positions. A group of 20 employees were tracked and the number of minutes of each video they watched was recorded. The sales manager then calculated how many workdays elapsed before the new associates made their first successful sale. Analyze this data and answer the question below: Using an alpha of 0.05 as your threshold for significance, what is the prediction equation for Days to first sale? (click here for larger image) Days to first sale = 23.244 -5.236*A - 3.761*B - 3.153*C + 7.749*D -0.41350*E + 3.145*AB Days to first sale = 22.326 - 4.817*A - 3.057*B + 7.185*D Days to first sale = 22.645 - 4.433*A - 2.890*B - 2.223*C + 7.672*D Days to first sale = 23.136 - 5.364*A - 3.726*B - 2.945*C + 7.737*D + 3.051*AB 26 / 51 A company has newly hired sales associates watch a series of five training videos that are each one hour long before starting in their new positions. A group of 20 employees were tracked and the number of minutes of each video they watched was recorded. The sales manager then calculated how many workdays elapsed before the new associates made their first successful sale. Analyze this data and answer the question below: In order minimize Days to first sale, how many minutes of Video 4 (factor D) should the sales associates watch? (click here for larger image) 42.263 0 8.3256 60 27 / 51 A company has newly hired sales associates watch a series of five training videos that are each one hour long before starting in their new positions. A group of 20 employees were tracked and the number of minutes of each video they watched was recorded. The sales manager then calculated how many workdays elapsed before the new associates made their first successful sale. Analyze this data and answer the question below: Which, if any, observations are influencing the model? (click here for larger image) Run #5 Run #7 None of them Run#15 28 / 51 A company has newly hired sales associates watch a series of five training videos that are each one hour long before starting in their new positions. A group of 20 employees were tracked and the number of minutes of each video they watched was recorded. The sales manager then calculated how many workdays elapsed before the new associates made their first successful sale. Analyze this data and answer the question below: What recommendations do you have to streamline the training program? (select all that apply) (click here for larger image) Eliminate video 5 (E) Have each associate watch video 4 (D) twice Eliminate video 2 (B) Eliminate video 3 (C) Eliminate video 1 (A) Eliminate video 4 (D) 29 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: What DOE design is recommended for this experiment? 23-1 fractional factorial design Box Behnken design Central Composite design L12 Screening design 30 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: Using an alpha of 0.10 as your threshold for significance, what factors are significant in the Y-hat model? (select all that apply) ABC CC C AA BB A BC AB AC B 31 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: Using an alpha of 0.10 as your threshold for significance, what factors are significant in the S-hat model? (select all that apply) ABC AC AB CC AA C A B BB BC 32 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: Based on the Y-hat marginal means plot, how does the average Customer Satisfaction score (the output) behave as the cabin temperature moves from the low setting to the high setting? Satisfaction is lower when temperature is at the low setting, then rises at the midpoint, and then falls again as it moves to the high setting Satisfaction is higher when temperature is at the low setting, goes down at the midpoint, and then rises again as it moves to the high setting Satisfaction is low when temperature is at the low setting, then rises as the temperature moves to the midpoint, and rises further as it moves to the high setting Satisfaction is high when temperature is at the low setting, then goes down as the temperature moves to the midpoint, and goes down further as it moves to the high setting 33 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: Based on the S-hat marginal means plot, how does standard deviation of Customer Satisfaction (the output) behave as the cabin lighting moves from the low setting to the high setting? The standard deviation starts high when cabin lighting is at the low setting, goes down at the midpoint, then goes up again at the high setting. The standard deviation starts high when cabin lighting is at the low setting, goes down at the midpoint and continues to go down at the high setting. The standard deviation starts low when cabin lighting is at the low setting, goes up at the midpoint, then goes down again at the high setting. The standard deviation starts low when cabin lighting is at the low setting, goes up at the midpoint and continues to go up at the high setting. 34 / 51 An aviation startup company is developing an electric plane for use on short commuter routes. They have successfully flown their plane in tests but now want to make it customer friendly. They will fly a set route multiple times with different aircraft “settings” and then survey the passengers about their satisfaction with the comfort of the flight. The following are the three factors they will experiment with. Due to power restrictions, they can’t maximize all settings at the same time. (click here for larger image) Analyze this data and answer the question below: What are the optimized settings that equally balance maximizing the average Customer Satisfaction score and minimizing its standard deviation? Speed = 277 knots, Cabin temperature = 75°F, Cabin lighting = 400 lux Speed = 300 knots, Cabin temperature = 68°F, Cabin lighting = 243 lux Speed = 300 knots, Cabin temperature = 70°F, Cabin lighting = 400 lux Speed = 300 knots, Cabin temperature = 65°F, Cabin lighting = 200 lux 35 / 51 A manufacturer of specialized textiles is trying to maximize the strength of the bond between two materials that they join with a proprietary adhesive. There are 9 factors they are experimenting with, as shown below: (click here for larger image) Analyze this data and answer the question below: Which factors are significant in Y-hat? (select all that apply) C A E AB I G B F D H 36 / 51 A manufacturer of specialized textiles is trying to maximize the strength of the bond between two materials that they join with a proprietary adhesive. There are 9 factors they are experimenting with, as shown below: (click here for larger image) Analyze this data and answer the question below: Which factors are significant in S-hat? (select all that apply) C H F A G AC D B E I AB 37 / 51 A manufacturer of specialized textiles is trying to maximize the strength of the bond between two materials that they join with a proprietary adhesive. There are 9 factors they are experimenting with, as shown below: (click here for larger image) Analyze this data and answer the question below: What immediate actions would you take to improve the process? (select all that apply) Train operators to only pre-heat the surface to 70° Train operators to only wait 5 minutes before pressing the surfaces together Train operators to always use only 10g of adhesive Train operators to make sure the press is held at 200psi during bonding 38 / 51 A manufacturer uses heat-sealed polystyrene to wrap parts for shipment to customers. They hold the seal time constant at 2 seconds, but conduct a DOE to better understand how the other two input variables: pressure (35 - 45 psi) and temperature (90°C -105°C) affect seal strength (measured in psi). Analyze this data and answer the question below (use an alpha of 0.05 as your threshold of significance): Which statement best describes the interaction in the Y-hat model? There is no significant interaction When temperature is set to 90°, the seal strength increases when pressure moves from the low setting to the high setting, but when temperature is 105°, the seal strength decreases when pressure moves from the low setting to the high setting. When temperature is set to 90°, the seal strength decreases when pressure moves from the low setting to the high setting, but when temperature is 105°, the seal strength increases when pressure moves from the low setting to the high setting. When pressure is at the low setting, temperature is not significant, but when pressure is at the high setting, temperature is significant 39 / 51 A manufacturer uses heat-sealed polystyrene to wrap parts for shipment to customers. They hold the seal time constant at 2 seconds, but conduct a DOE to better understand how the other two input variables: pressure (35 - 45 psi) and temperature (90°C -105°C) affect seal strength (measured in psi). Analyze this data and answer the question below (use an alpha of 0.05 as your threshold of significance): Which statement best describes the interaction in the S-hat model? When temperature is set to 90°, the standard deviation increases when pressure moves from the low setting to the high setting, but when temperature is 105°, the standard deviation decreases when pressure moves from the low setting to the high setting. There is no significant interaction When pressure is at the high setting, the standard deviation is insignificant When temperature is set to 90°, the standard deviation decreases when pressure moves from the low setting to the high setting, but when temperature is 105°, the seal strength increases when pressure moves from the low setting to the high setting. 40 / 51 A manufacturer uses heat-sealed polystyrene to wrap parts for shipment to customers. They hold the seal time constant at 2 seconds, but conduct a DOE to better understand how the other two input variables: pressure (35 - 45 psi) and temperature (90°C -105°C) affect seal strength (measured in psi). Analyze this data and answer the question below (use an alpha of 0.05 as your threshold of significance): Create a contour plot for the Y-hat model. The manufacturer would like achieve a seal strength above 65 psi, but would also prefer to limit the input pressure to no more than 42 psi. Based on what you see, is it possible to achieve both goals? No Yes 41 / 51 A retail store wants to see if the amount of the average customer sale is affected by the following variables: Time of day, Customer traffic, Day of week. They gather historical data from the previous five weeks and set up a custom design. (click here for larger image) Analyze this data and answer the question below: Using an alpha of 0.05 as your threshold of significance and following our rule of thumb for tolerances, optimize your model. Which factor(s) are significant? (check all that apply) AB A ABC B BB BC AC AA C 42 / 51 A retail store wants to see if the amount of the average customer sale is affected by the following variables: Time of day, Customer traffic, Day of week. They gather historical data from the previous five weeks and set up a custom design. (click here for larger image) Analyze this data and answer the question below: Using an alpha of 0.05 as your threshold of significance and following our rule of thumb for tolerances, optimize your model. Using the multiple response optimizer, which day is predicted to have the highest sales? Thursday Tuesday Wednesday Monday Friday Saturday 43 / 51 A retail store wants to see if the amount of the average customer sale is affected by the following variables: Time of day, Customer traffic, Day of week. They gather historical data from the previous five weeks and set up a custom design. (click here for larger image) Analyze this data and answer the question below: Using an alpha of 0.05 as your threshold of significance and following our rule of thumb for tolerances, optimize your model and generate a residual sheet. Which, if any, residuals concern you? None of the residuals are concerning Run #10 Run #9 Run #16 Run #1 44 / 51 A logistics engineer is setting up a new machine. There are 5 configurable settings and she would like to conduct a DOE to build a linear model but is concerned about how many samples she will need to gather. What design would you recommend? 25-1 Fractional Factorial Box Behnken Taguchi L18 25 Full Factorial 45 / 51 What is the main concern with "one-factor-at-a-time" experimentation? Two way interactions are always aliased with three way interactions It can't be used to study standard deviation It fails to identify interactions It can only be used with linear systems 46 / 51 If you are planning an experiment on a system but you're not sure if it behaves in a linear or non-linear way, which design is best? Taguchi L12 Box Behnken Central Composite 2 level full factorial 47 / 51 A manufacturer needs to measure the width of an assembly. The target width is 20cm, ±0.5. A series of sample measurements was taken and can be found here. What is the probable error of the measurement system? 0.3 0.7 0.1 0.5 48 / 51 A manufacturer needs to measure the width of an assembly. The target width is 20cm, ±0.5. A series of sample measurements was taken and can be found here. Based on your calculation of probable error, what concern, if any, do you have about the measurement system? The measurement tool is biased Based on the calculated probable error, a part measured at the target value of 20cm has a chance of being out-of-spec Poor reproducibility No concerns Not all of the sampled parts were in spec 49 / 51 A necessary condition for successful change efforts is: An active, engaged sponsor Extra time Printed documents describing the change 100% buy-in from all stakeholders at the start 50 / 51 The main question in people's minds when they become aware of a change is often: Who is responsible? What does my boss think? How does this change affect you? How does this change affect me? 51 / 51 A communications plan for a change effort must consider the following (select all that apply)? How much each person will be paid Who will deliver the message How you will manage resistance Who needs to receive communications about the change Your score is