S6-6 Prepare and analyze a scatter plot (Learning Objective 3)

Jones Oil and Lube is a car care center specializing in ten-minute oil changes. Jones Oil and Lube has two service bays, which limits its capacity to 3,400 oil changes per month.

The following information was collected over the past six months:

Month Number of Oil Changes Operating Expenses January....................................... 3,200 $36,400 February..................................... 2,600 $31,900 March......................................... 2,800 $32,850 April............................................ 2,700 $32,500 May............................................. 3,600 $37,000 June............................................ 2,900 $33,700 1. Prepare a scatter plot graphing the volume of oil changes (x-axis) against the company’s monthly operating expenses (y-axis). Graph by hand or use Excel.

2. How strong of a relationship does there appear to be between the company’s operating expenses and the number of oil changes performed each month? Explain.

Do there appear to be any outliers in the data? Explain.

3. Based on the graph, do the company’s operating costs appear to be fixed, variable, or mixed? Explain how you can tell.

4. Would you feel comfortable using this information to project operating costs for a volume of 3,800 oil changes per month? Explain.