the overhead costs at various levels of activity for Joey's Timber Company are as follows:

Month Machine Hours Total Overhead Costs

July 40,000 $ 186,200

August 60,000 $ 210,500

September 80,000 $ 260,000

October 50,000 $ 198,400

Total overhead costs are made up of electricity, depreciation of equipment and maintenance. The breakdown of these costs at the 40000 machine hour level of activity is:

Electricity (variable) $ 56,000

Depreciation of equipment (fixed) 65,000

Maintenance (mixed) 65,200

Total Overhead Costs $186,200

Joey needs to breakdown the maintenance cost into the fixed and variable components.

1. From the information above, estimate how much of September's overhead cost is made up by the maintenance cost.

2. Using the high-low method, estimate a cost formula for maintenance

3. Express the total overhead costs in the linear equation form Y = a + bX