Lean Six Sigma Black Belt Questions with Detailed Verified Answers

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Lean Six Sigma Black Belt Questions
with Detailed Verified Answers

Question:The primary focus of Six Sigma


Ans: quality and consistency


Question: The acronym for the Lean Six Sigma cycle


Ans: DMAIC


Question: What does the acronym DPMO represent?


Ans: Defects Per Million Opportunities


Question: The number of DPMO in a Six Sigma process.


Ans: 3.4


Question: What percent of the observations, data points, or events will fall
between plus and minus 1 standard deviation of the mean?


Ans: 68 Precent


Question: What percent of the observations, data points, or events will fall
within plus and minus 6 standard deviations of the mean?

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Ans: 99.9997 Percent


Question: A process generates a sample mean beyond the UCL. But the
process mean has not shifted. What type of error has been made?


Ans: Alpha


Question: What type of chart is used to monitor sample means, when the size
of the sample is between 12 and 25 and the data are continuous?


Ans: X-Bar Chart


Question: The statistical terms that define the quality expected by customers
and include on a process control chart.


Ans: Lower Specification Limit and Upper Specification Limit


Question: The type of process control chart in which sample means are
displayed and the data are continuous.


Ans: X-Bar Chart


Question: The type of process control chart that displays process variation
when the sample size is less than twelve and the data are continuous


Ans: R-Chart


Question: The distribution that describes the way in which sample means vary
around the population mean.

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Ans: Distribution of Sample Means


Question: The statistic that measures the variation in a distribution by taking
into consideration only the highest and lowest values in a dataset.


Ans: Range


Question: Purpose of the X-Bar chart.


Ans: To ensure that the process mean has not shifted, and that the process is
in-control.


Question: Another phrase for a process flow diagram that illustrates process
steps and delays.


Ans: Value Stream Map


Question: A term that represents the real cause of a problem.


Ans: Root Cause


Question: What does Y=f(x) represent?


Ans: The relationship between process inputs and process outputs. Y
represents outputs, and x represents inputs. Outputs are therefore a 'function
of' inputs.


Question: What is USL?

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Ans: Upper Specification Limit. The level above which output is considered to
be unacceptable by the customer. For example, service levels at a call center
where wait time is more than ten minutes.


Question: The meaning of COPQ.


Ans: Cost of Poor Quality. The 'total' costs incurred by the organization when
quality is less than desirable.


Question: Pareto Chart


Ans: A variation of the ordered histogram displaying the cumulative percent
that eliminating successive problem categories will contribute to solving the
overall set of problems expressed in the chart.


Question: Value Added


Ans: A concept in Lean that identifies the value added by a step in an
operational process. Value added is defined from the customer's point-of-
view. As long as the customer receives value from a process step, it is
considered "Value-Added."


Question: Can a process mean be changed by moving the LCL and UCL?


Ans: No. The process itself would have to be changed. A change in the LCL
and UCL would only change the alpha and beta errors.


Question: A goal when using a Value Stream Map analysis.