I need help figuring out this problem. I have been working on it for days and I cannot seem to get it. Any help would be greatly appreciated.

4. The beginning inventory and purchases of an item for the period were as follows:

Beginning inventory 6 units at $73 each
First purchase 10 units at $72 each
Second purchase 18 units at $74 each
Third purchase 10 units at $75 each

The company uses the periodic system, and there were 15 units in the inventory at the end of the period. Determine the cost of the 15 units in the inventory by each of the following methods, presenting details of your computations: (a) first-in, first-out; (b) last-in, first-out; (c) average cost.

Thank you in advance!

FIFO
BEG INV 6x73=438
PURCHASE 10x 72 =720
PURCHASE 13x 74 = 962
SOLD 29
THE 15 LEFT ARE COSTED AT 5 x74 = 370 AND 10 x75=750
ENDING INVENTORY ARE 15 UNITS = 1120
__________________________________________________ ________
LIFO
PURCHASE 10x75= 750
PURCHASE 18x74= 1332
PURCHASE 1x72= 72
SOLD 29
THE 15 LEFT ARE COSTED AT 9 x 72=648 AND 6 x73=438
ENDING INVENTORY ARE 15 UNITS = 1086
__________________________________________________ _________
AVERAGE COST
BEG INV 6x73=438
PURCHASE 10x72=720
PURCHASE 18x74 1332
PURCHASE 10x75=750
TOTAL 44 UNITS FOR A TOTAL OF $3240
3240/44= 73.64 EA UNIT
15 UNITS @ 73.64 = 1104.55 ENDING INVENTORY

jmancer, please do not just work out someone's homework for them. They are responsible for their own work. We are here to help them, not do it for them.