During a period, Department A finished and transferred 76,000 units to Department B. Of the 76,000 units, 15,200 were one-fifth complete with respect to direct labor at the beginning of the period and 49,500 were started and completed during the period. Also, during the period, 16,500 units were started but brought only to a stage of being three-fifths completed. Using the weighted-average inventory valuation method, the number of equivalent units of labor added by the end of the period was?