Exhibit 8-2 The Manager of a Grocery Store Has Taken a Random

question 30

Multiple Choice

Exhibit 8-2
The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took these 100 customers to check out was 3.0 minutes. It is known that the standard deviation of the checkout time is one minute.
-Refer to Exhibit 8-2. The 95% confidence interval for the average checkout time of all customers is

• A)3 to 5
• B)1.36 to 4.64
• C)2.804 to 3.196
• D)1.04 to 4.96

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Definitions:

Randomization

The process of making choices or selecting participants for a study randomly to eliminate bias and ensure impartiality.

Experimental Group

In research, a group of subjects who are exposed to the variable under study to assess its effect, as opposed to a control group.

Control Group

In experimental research, a group of subjects that does not receive the experimental treatment, allowing for a comparison to assess the effect of the treatment.

Operationalization

The process of defining measurement criteria for abstract concepts to enable their empirical, quantitative measurement.