The answer is 3.9. In fraction form the answer is 89/10. In mixed fraction form the answer is 8 9/10
Answer:
The correct answer is 10 for lowest average cost and the cost function is 0.2 + 75x + 20.
Step-by-step explanation:
Average cost function is given by = = C(x) = 0.2x + +75.
For minimizing we need to find C(x) = 0.
⇒ C(x) = 0.2 - .
⇒ = 0.2
⇒ = 100.
⇒ x = ±10
⇒ x = 10 ; cost cannot be negative.
Second order derivative is positive which implies the average cost minimizes.
Original cost function is given by C(x) × x = 0.2 + 75x + 20.