________________________ chart is used to count data (defects) with variable sub groups.
________________________ chart is used to count data (defects) with variable sub groups.
A u chart is used to count data (defects) with variable subgroups. This chart is suitable for monitoring the number of defects per unit in samples of varying sizes. The np chart is not appropriate for variable subgroup sizes, X-bar and S chart are used for continuous data and process variation, and the c chart monitors the number of defects in fixed subgroup sizes.
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