Exhibit 9-9
the Sales of a Grocery Store Had an Average

question 77

Multiple Choice

Exhibit 9-9
The sales of a grocery store had an average of $8,000 per day. The store introduced several advertising campaigns in order to increase sales. To determine whether or not the advertising campaigns have been effective in increasing sales, a sample of 64 days of sales was selected. It was found that the average was $8,300 per day. From past information, it is known that the standard deviation of the population is $1,200.
-Refer to Exhibit 9-9. The correct null hypothesis for this problem is

• A)\(\mu\) < 8000
• B)\(\mu\) > 8000
• C)\(\mu\) = 8000
• D)\(\mu\)> 8250

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Definitions:

Social Psychology

The scientific study of how individuals think, feel, and behave in social contexts.

External Validity

The degree to which a study's findings can be applied to different scenarios and various individuals.

Theoretical

Pertaining to a system of ideas intended to explain something, based on general principles independent of the thing to be explained.

Social Psychology

The scientific study of how individuals think, influence, and relate to one another within a social context.