Equivalent Units of Production and Related Costs The charges to Work in Process-Assembly Department for a period, together with information concerning production, are as follows. All direct materials are placed in process at the beginning of production. Bal., 9,000 units, 40% completed Direct materials, 40,000 units @ $6.80 Direct labor Factory overhead. Bal, ? units, 30% completed Determine the following: Work in Process-Assembly Department 72,360 To Finished Goods, 41,500 units 272,000 80,000 40,450 a. The number of units in work in process inventory at the end of the period. units: