Answer:
(a) $496
(b) $945
(c) $480
Step-by-step explanation:
Jan 1, Inventory = $435
August 7, Purchase = $510
December 11, Purchase = $465
Total units = 47 units
Total purchase = $1,410
Average cost = Total purchase ÷ Total units
 = $1,410 ÷ 47 units
 = $30 
Units sold = Total units - Ending inventory
 = 47 - 16
 = 31 units
(a) FIFO:
Merchandise inventory = 16 units × $31
 = $496
(b) LIFO:
Merchandise inventory = (15 units × $29) + (17 units × $30)
 = $435 + $510
 = $945
(c) Weighted average cost method:
Merchandise inventory: 
= Ending inventory × Average cost
= 16 units × $30
= $480