I don't understand how to get the right answer. If someone can show how to get the right answer step by step in the style of the second screenshot, I would greatly appreciate it.

Question 8 0 / 10 points Addison, Inc. uses a perpetual inventory system and sells a product for $50. The following is information about one inventory item for the month of September: Sep. 1 Inventory 20 units at $20 4 Sold 10 units 10 Purchased 30 units at $25 17 Sold 20 units If Addison uses FIFO, using a perpetual system, calculate the cost of goods sold for September. $700 X $500 $1,500 $650 Purchases Inventory Cost of Goods Sold Total Quantity Unit Cost Cost Total Cost Total Cost Date Quantity Unit Cost Quantity Unit Cost