Castle Company uses the FIFO method in its process costing system. In the Cutting Department in June, units were four-fifths complete with respect to conversion in the beginning work in process inventory and one-third complete with respect to conversion in the ending work in process inventory. Other data for the department for June follow: Units. .. Conversion cost Beginning work in process inventory 25,000 30,000 Units started into production, and cost incurred during the month 140,000 175,000 Units completed and transferred out 135,000 The cost per equivalent unit for conversion cost is closest to