wa eup...O'Malley Corp uses a weighted average process costing system. Material is added at the beginning of the production process and overhead is applied on the basis of direct labor. O'Malley records indicate that 70,000 units were in process at the beginning of may 2013; these units were 30% complete as to conversion. In May, the company started 445300 and completed 427500 units. May's ending inventory was 35% complete as to conversion