Edexcel C2 2010 June — Question 9

Exam BoardEdexcel
ModuleC2 (Core Mathematics 2)
Year2010
SessionJune
TopicGeometric Sequences and Series

9. The adult population of a town is 25000 at the end of Year 1. A model predicts that the adult population of the town will increase by \(3 \%\) each year, forming a geometric sequence.
  1. Show that the predicted adult population at the end of Year 2 is 25750.
  2. Write down the common ratio of the geometric sequence. The model predicts that Year \(N\) will be the first year in which the adult population of the town exceeds 40000.
  3. Show that $$( N - 1 ) \log 1.03 > \log 1.6$$
  4. Find the value of \(N\). At the end of each year, each member of the adult population of the town will give \(\pounds 1\) to a charity fund. Assuming the population model,
  5. find the total amount that will be given to the charity fund for the 10 years from the end of Year 1 to the end of Year 10, giving your answer to the nearest \(\pounds 1000\).