Question

Some of the information found on a detail inventory card for Concord Inc. for the first month of operations is as follows. Received Balance, No. of Units Issued, No. of Units No. of Units 1,700 Date January Unit Cost $3.39 1,200 1,100 3.62 1,500 3.73 1,000 800 1,100 1,700 500 1,600 600 1,300 200 2,000 700 2,800 1,000 1,800 3.84 1,300 2,100 3.96 1,800
I just need to figure out what the moving average cost is for the ending inventory. And if you could include an explanation in how you found the average cost on the 18th that would be great because so far I have this. Just so I can understand how to determine the avg cost for a date that has both a purchase and selling of goods.

Date	Buy	COGS	UNITS	AVG Cost	Inventory Cost
2	1700*3.39	0	1700	3.39	5763
7		1200*3.39=4068	500	3.39	1695
10	1100*3.62		1600	3.5481	5677
13		1000*3.5481	600	3.5481	2129
18	1500*3.73	800*?	1300

Answer 1

W.Avg		Purchases			Cost of Goods Sold			Ending Inventory
		Quantity	Unit Cost	Amount	Quantity	Unit Cost	Amount	Quantity	Unit Cost	Amount
Jan-02	Purchase	1700	$            3.39	$           5,763				1700	$           3.39	$         5,763
Jan-07	Sales				1200	$           3.39	$           4,068	500	$           3.39	$         1,695
Jan-10	Purchase	1100	$            3.62	$           3,982				500	$           3.39	$         1,695
								1100	$           3.62	$         3,982
					Average			1600	$           3.55	$         5,677
Jan-13	Sales				1000	$           3.55	$           3,548	600	$           3.55	$         2,129
Jan-18	Purchase	1500	$            3.73	$           5,595				600	$           3.55	$         2,129
								1500	$           3.73	$         5,595
					Average			2100	$           3.68	$         7,724
Jan-18	Sales				800	$           3.68	$           2,942	1300	$           3.68	$         4,782
Jan-20	Sales				1100	$           3.68	$           4,046	200	$           3.68	$            736
Jan-23	Purchase	1800	$            3.84	$           6,912				200	$           3.68	$            736
								1800	$           3.84	$         6,912
					Average			2000	$           3.82	$         7,648
Jan-26	Sales				1300	$           3.82	$           4,971	700	$           3.82	$         2,677
Jan-28	Purchase	2100	$            3.96	$           8,316				700	$           3.82	$         2,677
								2100	$           3.96	$         8,316
					Average			2800	$           3.93	$      10,993
Jan-31	Sales				1800	$           3.93	$           7,067	1000	$           3.93	$         3,926
	Total			$         30,568			$         26,642			$         3,926

Average Cost is calculated after every purchase.
For Jan 18, average is calculated after every purchase.