htlowb age 224 of 734 Contents costs incurred, along with the number of maintenance and repair jobs completed each month The data are shown below: Jobs Month January February March... April...... May June, July August.... September... October.. Repair Costs $22.000 $18.000 $7600 $20,000 $24,000 $22.400 $ 16,000 $ 12,800 $ 13,600 $ 9600 Required: 1. Using Microsoft Excel, prepare a scattergram by plotting jobs performed and repair costs on a graph. Fit a straight line to the plotted points using the "add trendline feature in Microsoft Excel. Do repair costs appear to be related to the number of jobs completed in a month? Explain. Using the high-low method, estimate a cost formula for repair costs. Express the formula in the form Y= a + bX. 3. Now assume the manager wants to predict costs for a month where 600 jobs will be com- pleted. Should you use the formula developed above to predict costs for a 600-job month? Why or why not? PROBLEM 3-15 High-Low Method: Predicting Cost |LO1. LO2]