The following is a system of simultaneous linear equations to allocate costs using the reciprocal method. Matrix algebra is not required. The following costs were incurred in three operating departments and three service departments in Westmoreland Company. Department Subassemblies Direct Costs Label $565,000 P1 Final assembly 790,000 P2 Marketing 300,000 P3 Building occupancy 100,000 $1 Research & development 135,000 82 Supervision 60,000 83 Use of services by other departments is as follows. User Departments Sub- Final Service Cost Center assemblies Assembly Marketing Building Occupancy Building occupancy 0.30 0.25 0.20 R&D 0.10 Supervision 0.15 R&D 0.50 0.50 Supervision 0.30 0.30 0.20 0.10 0.10 The equation for department P3 (marketing) is