If a process has 3-sigma control limits, what percentage of the sample averages are expected to fall within these limits if the process only has natural variations?
Explanation
Control chart limits are based on the properties of the normal distribution. For a process that is in statistical control, it is expected that 99.73 percent of all sample means will naturally fall within control limits set at plus and minus three standard deviations from the center line.
Other questions
What is the primary objective of a statistical process control (SPC) system?
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Which statement best describes the central limit theorem as it applies to statistical process control?
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What is the key difference between an x-chart and a p-chart?
In acceptance sampling, what does the Acceptable Quality Level (AQL) represent?
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In the context of control charts, what is a run test used for?
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