Answer:
634 units
Step-by-step explanation:
Given that,
Produce at the rate, p = 960
Rate of assemble hair dryers per day, d = 380 per day
Batches of units produced, Q0 = 2100
Maximum Inventory:

= 1268.75
Therefore,
Average Inventory = Maximum Inventory ÷ 2
Average Inventory = 1268.75 ÷ 2
= 634.375
= 634 units