Why the ending inventory on Mar 1 is 1, Mar 9 is 2, Mar 22 is 2, and Mar 30 is 9.

Greg's Bicycle Shop has the following transactions related to its top-selling Mongoose mountain bike for the month of March. Greg's Bicycle Shop uses a periodic inventory system. Unit Cost $ 250 Total Cost $ 5,000 270 Date March March March March March March March Transactions Beginning inventory Sale ($400 each) Purchase Sale ($450 each) Purchase Sale $475 each) Purchase 1 5 9 17 22 27 30 Units 20 15 10 8 10 12 9 2,700 280 2,800 300 2,700 $13,200 For the specific identification method, the March 5 sale consists of bikes from beginning inventory, the March 17 sale consists of bikes from the March 9 purchase, and the March 27 sale consists of four bikes from beginning inventory and eight bikes from the March 22 purchase