# Math Help - revenue problem

1. ## revenue problem

An airline offers summer flights from toronto to london for groups of students. a minimum of 80 students must sign up for each flight, at a round-trip fare of $2400 per person. however, the airline will reduce the fare by$10 for each additional student who joins the flight. what number of passengers will give the airline the greatest revenue?

2. Originally Posted by euclid2
An airline offers summer flights from toronto to london for groups of students. a minimum of 80 students must sign up for each flight, at a round-trip fare of $2400 per person. however, the airline will reduce the fare by$10 for each additional student who joins the flight. what number of passengers will give the airline the greatest revenue?
let x = number of additional students

R(x) = (2400-10x)(80+x)

so, maximize R(x) ... remember the number of students is 80+x

3. Originally Posted by skeeter
let x = number of additional students

R(x) = (2400-10x)(80+x)

so, maximize R(x) ... remember the number of students is 80+x
so R(x)= -10x^2 + 1600x + 192000

R'(x)=-20x+1600 indicating a max

setting R'(x)=0

-20x+1600=0
-20x=-1600
x=80

where do i go from here?

4. how do i finish the problem from here?

5. Originally Posted by euclid2
how do i finish the problem from here?