Comparisons of a simplified costing system with an activity- based system (continuation of E9-5 and E9-6) Prior to instituting an activity-based costing system, Harris and Whelan, the attorneys in E9-5 and E9-6, utilized a simplified costing system with one direct cost category, professional labor, and one indirect cost category, professional support. The aver- age wage rate for professional labor was $75 per hour, and the overhead rate for professional support was $67.50 per profes- sional labor hour. Compute the job cost for Carolyn Goode, the client in E9-6, using the simplified costing system, and determine the differ- ence between it and the job cost using activity-based costing in E9-6 and discuss the reasons for the difference.