Stickforth Company uses weighted average process costing. At the beginning of the month, there were 4,000 units in process, 80% complete with respect to material and 60% complete with respect to conversion costs. 20,000 units were started during the month, 21,000 units were completed and there were 3,000 units in the ending work in process inventory that were 100% complete with respect to material and 30% complete with respect to conversion costs. What are the equivalent units to be used in calculating the cost per unit for materials?