Optima Company uses a periodic inventory system. On July 1, 2006, Optima purchased 150 units of inventory at a cost of $3.00. On July 15, 2006, Optima purchased 200 units at a cost of $3.50. On July 30, 2006, Optima sold 175 units. If Optima uses a weighted average inventory cost flow assumption, then the ending inventory appearing on the balance sheet on July 31, 2006 would be

Need average unit cost first: (150x3+200x3.5)/(150+200), then use the unit price times the units that are left after the sale on 7/30/06.