OCR H240/01 2021 November — Question 2

Exam BoardOCR
ModuleH240/01 (Pure Mathematics)
Year2021
SessionNovember
TopicSimultaneous equations

2 Alex is comparing the cost of mobile phone contracts. Contract \(\boldsymbol { A }\) has a set-up cost of \(\pounds 40\) and then costs 4 p per minute. Contract \(\boldsymbol { B }\) has no set-up cost, does not charge for the first 100 minutes and then costs 6 p per minute.
  1. Find an expression for the cost of each of the contracts in terms of \(m\), where \(m\) is the number of minutes for which the phone is used and \(m > 100\).
  2. Hence find the value of \(m\) for which both contracts would cost the same.