solution

A marketing manager for a large cafeteria chain wished to investigate sales of coffee (i.e., sales is the variable she is trying to understand). Fourteen cafeterias that were similar in such respects as volume of business, type of clientele, and location were chosen for data collection. Data were collected on sales of coffee (in hundreds of gallons) and the number of coffee dispensers within the cafeteria. The results are shown below.

Sales	Number of Dispensers
559.1	1
557.8	1
711.1	2
691.6	2
748.8	3
766.7	3
847.1	4
810.3	4
836.8	5
842	5
908	6
858.5	6
957.4	7
936.4	7

Create a scatter plot and then fit a quadratic model to predict sales from the number of dispensers. If we define y to be sales (in hundreds of gallons) and x to be the number of dispensers, what is the correct quadratic model?

answer choices:

y=0.016x-8.569

y=-6.899x²+112.72x+475.07

y=2.645×10^-5x²-0.0238x+5.932

y=57.529x+557.857

y=570.342x^0.255