It is to be determined that the call center access time is in statistical control. Concept Introduction: The X-chart is used to determine the central tendency of the process. By using the X-chart it easy to determine the abnormalities of the process along with the errors which are responsible for these errors.

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Chapter 3, Problem 27P

(a)

Summary Introduction

Interpretation: It is to be determined that the call center access time is in statistical control.

Concept Introduction:

The X-chart is used to determine the central tendency of the process. By using the X-chart it easy to determine the abnormalities of the process along with the errors which are responsible for these errors.

(b)

Summary Introduction

Interpretation: The capability of the process is to be determined when three-sigma performance is desired.

Concept Introduction:

The X-chart is used to determine the central tendency of the process. By using the X-chart it easy to determine the abnormalities of the process along with the errors which are responsible for these errors.

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