Answer:
Closing inventory = 54,000 units
Step-by-step explanation:
The difference between profit under variable costing and under absorption costing is simply the value of the change in inventory.
Usually, a decrease in inventory would cause profit under absorption costing to be lower . This is so because cost of goods sold would become higher leading to a lower profit
Difference in profit = POAR × change inventory
POAR- fixed overhead cost per unit- $10,
Difference in profit - $120,000
let the change inventory be y
120,000 = 30 × y
y= 120,000/30
y = 4000 units
Inventory at the end = opening inventory + change inventory
= 50,000 + 4000
= 54,000 units
Note; An increase in inventory will produce a higher profit using absorption costing. Hence, we added the change inventory to the opening inventory, to reflect an increase in inventory