I dont understand last part, Finished goods inventory 3/31/2017 ? Help me please

Cal Nelson recently took over as the controller of Archer Brothers Manufacturing, Last month, the previous controller left the company with little notice and left the Bocounting records in disarray. Cal needs the ending inventory balances to report first-quartor numbers. For the previous month (March 2017) Ron was able to piece together the following Information: (Click the icon to view the information for March 2017.) Read the requirements First, solve for (3) direct materials inventory, 3/31/2017, then solve for (2) work in process inventory, 3/31/2017, and finally solve for (1) finished goods inventory, 3/31/2017 Direct materials inventory, 3/1/2017 12,000 150.000 0 Data Table Direct materials purchased Direct materials available for use 162,000 Direct materials inventory, 3/31/2017 72000 Direct materials purchased $ 150,000 90,000 Direct materials used 39,000 Work-in-process inventory 3/1/2017 290,000 $ Direct materials inventory, 3/1/2017 12,000 Conversion costs 380,000 $ Finished goods inventory, 3/1/2017 120,000 Total manufacturing costs added during the period 39,000 Conversion costs $ 290,000 Work-in-process inventory, 3/1/2017 $ 380,000 419,000 Total manufacturing costs added during the period Manufacturing costs to account for 3 times direct materials used 149,000 Cost of goods manufactured Work-in-process inventory, 3/31/2017 10% 270.000 Gross margin as a percentage of revenues $ 430,000 Cost of goods manufactured 120,000 Revenues Finished goods Inventory, 3/1/2017 390,000 Cost of goods available for sale Finished goods inventory 3/31/2017 387,000 Cocoada sold en Print Done 3,000