Department E had $4,000$ units in work in process that were $40\%$ completed at the begining of the period at a cost of $12,500.$ During this period $,14,000$ units of direct marerial were added to a cost of $$28,700,$ and $$15,000$ units were completed. At the end of the period, $3,000$ units were $75\%$completed. All material are added at the begining of the process.. Direct labor was $$32,450$ and factory overhead was

$$18,710.$the number of equvalent units of production for the period for conversuon if the first in$,$ first outt method is used to cost inventories was.