"A telephone company in   a town has 500 subscribers on its list and collects fixed charges
Channel: Doubtnut
Date: 28/06/2020

"A telephone company in
 
  a town has 500 subscribers on its list and collects fixed charges of Rs 300
 
  per subscriber. The company proposes to increase the annual subscription and
 
  it is believed that every increase of Rs 1 one subscriber will discontinue
 
  the service. Find what increase will bring maximum revenue?"