Answer:
64,925
Minimum occurs at x = 0 when no chairs are sold. The price is $0.
Explanation:
solution
Let x be the number of chair greater than 500. Then price is
P = (130-0.25*x)(500 +x)
For critical point,
P'(x) = -0.5x + 15 = 0
From here, we get x = 30. Using second derivative test, P"(x) = -0.5 for all x so global maximum occurs as the function is concave downward. The price is
P(30) = (130 - 0.25*30)(500 + 30) = $64,925
Minimum occurs at x = 0 when no chairs are sold. The price is $0.