Explanation:
The computation of the ending inventory using the each method is shown below:
a. FIFO
Since the 57 units is in physical inventory so 40 units should be taken at $357 i.e from latest purchase and the remaining 17 units is at $342
= 40 units × $357 + 17 units × $342
= $20,094
b. LIFO
Since the 57 units is in physical inventory so 20 units should be taken at $360 and the rest 37 units at $342
= 20 units × $360 + 37 units × $342
= $19,854
c. Weighted average cost method
= Weighted average cost per unit × ending inventory units
where,
Weighted average cost per unit is
= $110,400 ÷ 320 units
= $345
And, the ending inventory units is 57 units
So, the ending inventory is
= 57 units $345
= $19,665