Activity-based costing, manufacturing. Open Doors, Inc., produces two types of doors, interior and exterior. The company’s simple costing system has two direct cost categories (materials and labor) and one indirect cost pool. The simple costing system allocates indirect costs on the basis of machinehours. Recently, the owners of Open Doors have been concerned about a decline in the market share for their interior doors, usually their biggest seller. Information related to Open Doors production for the most recent year follows:

The owners have heard of other companies in the industry that are now using an activity-based costing system and are curious how an ABC system would affect their product costing decisions. After analyzing the indirect cost pool for Open Doors, six activities were identified as generating indirect costs: production scheduling, material handling, machine setup, assembly, inspection, and marketing. Open Doors collected the following data related to the indirect cost activities:

Marketing costs were determined to be 3% of the sales revenue for each type of door.
Required
1. Calculate the cost of an interior door and an exterior door under the existing simple costing system. 
2. Calculate the cost of an interior door and an exterior door under an activity-based costing system.
3. Compare the costs of the doors in requirements 1 and 2. Why do the simple and activity-based costing systems differ in the cost of an interior and exterior door?
4. How might Open Door, Inc., use the new cost information from its activity-based costing system to address the declining market share for interiordoors?