KS4/KS5 Maths Convergence investigation

This investigation (includes teacher notes and worksheets) is suited to very able KS4 groups and those in KS5 studying Maths. It covers the topics of convergence, subject of a formula and even can be expanded to iteration for more advanced learners.

Pupils are given a starting value of a sequence, which they multiply by 3, add 10 to then and finally divide by 4 to generate the next term in the sequence. They then multiply this value by 3, add ten to it and divide by 4 to get the next term and so forth, generating the sequence in an iterative manner until the sequence converges.

The goal of this investigation is to find a relationship between the initial starting value of the sequence and that which it converges to. This can be explained in a satisfying algebraic way using subject of the formula although pupils may offer other alternative explanations.