Answer:
The maximum revenue is $54,000 for 40 unsold seat plane.
Step-by-step explanation:
We are given the following in the question:
A charter flight charges a fare of $300 per person plus $15 per person for each unsold seat on the plane. The plane holds 100 passengers. Let x represent the number of unsold seats.
Total number of seats occupied = 100 - x
Revenue is given by
[tex]R(x) = (300+15x)(100-x)\\R(x) = 30000 + 1200x -15x^2[/tex]
First, we differentiate R(x) with respect to x, to get,
[tex]\dfrac{d(R(x))}{dx} = \dfrac{d(30000 + 1200x -15x^2)}{dx} = 1200 - 30x[/tex]
Equating the first derivative to zero, we get,
[tex]\dfrac{d(R(x))}{dx} = 0\\\\1200 - 20x= 0\\x = 40[/tex]
Again differentiation R(x), with respect to x, we get,
[tex]\dfrac{d^2(R(x))}{dx^2} = -30[/tex]
At x = 40
[tex]\dfrac{d^2(R(x))}{dx^2} < 0[/tex]
Thus, by double differentiation test maxima occurs at x = 40 for R(x).
Maximum revenue:
[tex]R(40) = (300+15(40))(100-40) = 54000[/tex]
Thus, maximum revenue is $54,000 for 40 unsold seat plane.
The attached image shows the graph for the total revenue received for the flight