5-INVENTORY COSTING USING THE FIFO METHOD 1. RathCo starts up in 20X8 and decides to use FIFO costing under the periodic method. During 20X9 it makes the following purchases: Purchase date Units purchased Unit cost Total cost January 15 600 $16 $ 9,600 April 12 2,400 $17 40,800 June 7 3,000 $19 57,000 August 25 1,300 $22 28,600 September 5 5,000 $25 125,000 December 11 900 $27 24,300 Total 13,200 $285,300 RathCo's 20X8 year-end physical count shows 4,000 units that cost $60,000. Its 20X9 physical count shows 2,600 units. a. What is RathCo's 20X9 ending inventory? b. COGS