Can someone please break this down for me. I have seen similar questions, but I am still having some confusion.

Cunumber sells a snowboard EZSlide, that is popular with snowboard enthusiasts. The following is information relating to Cullumber's beginning inventory and purchases of EZslide snowboards during September. During the same month, 106 EZslide snowboards were sold. Cullumber uses a periodic inventory system. Date Units Unit Cost Total Cost 11 $111 Explanation Inventory Purchases Purchases $ 1,221 5,358 47 Sept. 1 Sept. 12 Sept. 19 Sept. 26 114 49 115 5,635 Purchases 21 116 2,436 Totals 128 $14,650 Compute the ending inventory at September 30 and the cost of goods sold using the FIFO, LIFO, and average-cost methods. (Round per unit cost to 3 decimal places, e.g. 15.647 and final answers to O decimal places, e.g. 5,125.) FIFO LIFO Average-cost The ending inventory at September 30 $ $ $ Cost of goods sold $ $ $