Use the traditional method in testing the hypothesis in the problems below. In each
problem, state the following:
d. Make the decision
e. Summarize the result
The manager of the cosmetics section of a large department store wants to determine whether newspaper advertising really does affect sales. For her experiment, she randomly selects 15 items currently in stock and proceeds to establish a baseline. The 15 items are priced at their usual competitive values, and the quantity of each item sold for a 1-week period is recorded. Then, without changing their price, she places a large ad in the newspaper, advertising the 15 items. Again, she records the quantity sold for a 1-week period. The results follow.
Item 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
No. of Items Sold Before Ad 25 18 3 42 16 20 23 32 60 40 27 7 13 23 16
No. of Items Sold After Ad 32 24 7 40 19 25 23 35 60 43 28 11 12 32 28
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