OCR MEI AS Paper 1 2021 November — Question 11

Exam BoardOCR MEI
ModuleAS Paper 1 (AS Paper 1)
Year2021
SessionNovember
TopicExponential Functions

11 On the day that a new consumer product went on sale (day zero), a call centre received 1 call about it. On the 2nd day after day zero the call centre received 3 calls, and on the 10th day after day zero there were 200 calls. Two models were proposed to model \(N\), the number of calls received \(t\) days after day zero.
Model 1 is a linear model \(\mathrm { N } = \mathrm { mt } + \mathrm { c }\).
  1. Determine the values of \(m\) and \(c\) which best model the data for 2 days and 10 days after day zero.
  2. State the rate of increase in calls according to model 1.
  3. Explain why this model is not suitable when \(t = 1\). Model 2 is an exponential model \(\mathbf { N } = e ^ { 0.53 t }\).
  4. Verify that this is a good model for the number of calls when \(t = 2\) and \(t = 10\).
  5. Determine the rate of increase in calls when \(t = 10\) according to model 2 .