a) An airline will fill 100 seats of its aircraft at a fare of $200. For every $5 increase in the fare, the plane loses two passengers. For every decrease of $5, the company gains two passengers. What price maximizes revenue?

How Can I determine the number of passengers?

1 Answer
Jul 28, 2017

Fare of #$225# mximises revenue at #$20,250#. Number of passengers are #90#.

Explanation:

Let the fare br #f# and number of passengers be #p#. If #f# increases by #5#, #p# decreases by #2# and hence

#(Deltaf)/(Deltap)=-5/2# and relation between #f# and #p# is

#2f+5p=2xx200+5xx100=900# or #f=-5/2p+450#

and revenue #R# is given by #R=fxxp=-5/2p^2+450p#

and revenue maximises when #(dR)/(df)=-5p+450=0# or #p=90#

At this fare, number of passengers are #-5/2xx90+450=225#

and revenue is #20250#

graph{y+(5/2)x^2-450x=0 [0, 200, 18507, 20612]}