Consider a Service Process Such as a Fast Food Drive

question 128

Multiple Choice

Consider a service process such as a fast food drive through window. The target for a customer's waiting time is 3.0 minutes. A manager observes the process and randomly collects a sample of four waiting times each hour over a 12 hour period. The sum of the range for each of the 12 samples is 18.0. The UCL for the process control chart reporting variability within the samples is

• A) 3.4
• B) 4.5
• C) 5.6
• D) 6.8

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Definitions:

Control Chart

A graphical tool used in process control to display how a process changes over time, highlighting whether the process stays within predetermined control limits.

Sample Means

The arithmetic average of a set of values or observations, derived from a subset of a larger population.

Control Limits

The boundaries of acceptable variation in a process, used in statistical process control charts.

Chance Variation

The unpredictable fluctuations or differences that are observed in different samples from the same population, even under the same conditions.