Historically, the Average Time to Service a Customer Complaint Has $\bar{x}$

question 76

Multiple Choice

Historically, the average time to service a customer complaint has been 3 days and the standard deviation has been 0.50 day. Management would like to specify the control limits for an $\bar{x}$ chart with a sample size of 10- and 3- sigma limits. Suppose the average service time from the next 10 samples yielded the following result: 3.2, 2.1, 3.6, 2.8, 3.9, 3.5, 2.7, 4.1, 2.6, and 3.3 days. What conclusion can be drawn?

• A) Assuming the process variability is in control, the process average is also in statistical control.
• B) Assuming the process average is in control, the process average is out of statistical control.
• C) The sample size should be increased.
• D) No conclusion can be drawn because there is insufficient data.

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Definitions:

CPI

An index measuring the average change over time in the prices paid by urban consumers for a market basket of consumer goods and services.

Consumer Price Index

An index measuring the change over time in the price level of a market basket of consumer goods and services purchased by households.

Purchasing Power

The real value of money in terms of the quantity of goods or services that one unit of money can buy.

Annual Interest Rate

The percentage rate at which interest is charged or paid on an amount over a year.