Unit 3 includes bivariate data analysis, growth and decay in sequences and graphs and networks. Bivariate data analysis involves identifying, analysing and describing associations between pairs of variables, including using the least-squares method. Growth and decay in sequences employs recursion to generate sequences to model and investigate growth and decay in discrete situations. Graphs and networks introduce students to the notion of a collection of points and interconnecting lines to represent a network.

Unit 4 includes time series analysis, loans, investments and annuities, and networks and decision mathematics. Time series analysis continues students’ study of statistics by introducing concepts and techniques of time series analysis. Loans and investments aims to provide students with sufficient knowledge of financial mathematics to solve practical problems associated with taking out or refinancing a mortgage and making investments. Networks and decision mathematics’ uses networks to model and aid decision making in practical situations.