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Penodic inventory by three methods; cost of poods sold The units of an item avaloble for sale during the year were as follows: There are 80 units of the item in the physical inventory at December 21 . The periodic inventory system is used: Determine the ending invertory cost and the cost of goods sold by three methods. In your calculations round average unit cost to the nearest cent, and round all other calculations and your final answers to the nearest dollar