Edexcel P3 2023 October — Question 6

Exam BoardEdexcel
ModuleP3 (Pure Mathematics 3)
Year2023
SessionOctober
TopicExponential Equations & Modelling

  1. An area of sea floor is being monitored.
The area of the sea floor, \(S \mathrm {~km} ^ { 2 }\), covered by coral reefs is modelled by the equation $$S = p q ^ { t }$$ where \(p\) and \(q\) are constants and \(t\) is the number of years after monitoring began.
Given that $$\log _ { 10 } S = 4.5 - 0.006 t$$
  1. find, according to the model, the area of sea floor covered by coral reefs when \(t = 2\)
  2. find a complete equation for the model in the form $$S = p q ^ { t }$$ giving the value of \(p\) and the value of \(q\) each to 3 significant figures.
  3. With reference to the model, interpret the value of the constant \(q\)