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Wheeler Engine Repairs provides maintenance and repair services for small engines such as those found in lawn mowers, power saws, and snow throwers. The repair shop costs include the salaries for the mechanics, insurance and depreciation on the repair equipment, materials and parts used for the jobs, and utilities. The repair shop manager would like to develop a model for predicting repair costs and over the past 10 months has carefully recorded the total repair costs incurred, along with the number of maintenance and repair jobs completed each month. The data are shown below: Month January February March April May June July August September October Jobs Repair Costs 440 $ 44,000 360 $ 36,000 320$ 35,200 400 $ 40,000 520 $ 48,000 480$ 44,800 280 $ 32,000 240 $ 25,600 200 $ 27,200 160 $ 19,200 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 Required: Using the high-low method, estimate a cost formula for repair costs. Express the formula in the form Y = a + bx. High level of activity Low level of activity Change Activity Cost 520 $ 48,000 160 19,200 360 $ 28,800 Low level of activity $160.00 Computing the fixed cost using the high level of activity: High level of activity $48,000 Variable cost per unit: 83,200 Total fixed cost :-$35,200 Cost formula: Y = -$35,200 $160.00 X