Education Technology

Mathematics lessons for IB® Diploma Programme

Applications and Interpretation | Numbers and Algebra

Statistics: Does a Correlation Exist?


  • Understand the limiting behaviour as n approaches infinity in a geometric sequence and its dependence on the value of the common ratio
  • Use geometric sequences in contexts involving geometric growth or decay, such as compound interest.


  • Sequence
  • Series
  • Sum
  • Infinity

About the Lesson

Students begin by exploring the Pebbling the Chessboard problem. It is not long before students challenge whether or not the problem has a solution. Rather than continuing with trial and error attempts, numbers are used to record the moves, leading to the discovery that a geometric sequence is produced. The sum of the terms in the sequence holds the answer to the problem.

A PowerPoint file is also included so that teachers can demonstrate the problem (and solution) to students.