Goodyear Corporation uses a process cost system in manufacturing its tires for the bicycle industry. Materials are added at the beginning of the process and conversion costs are applied evenly throughout the process. At the beginning of March, the work-in-process is 40% complete and at the end of the month, it is 60% complete. Spoilage is detected at the end of the process. Other data for the month include: Beginning WIP inventory 1,600 units Units started 20,000 units Units placed in finished goods 12,000 units Ending WIP inventory 1,200 units Normal spoilage of units finished 20% Conversion costs P604,800 Cost of direct materials 600,000 Beginning WIP costs Materials 60,000 Conversion 60,480 Use weighted-average method.