Formula

This link explains how we substitute values into formulae.  (and includes some test questions)

And this explains why we use formulae.


Remember:
x² = x time x
x³ = x times x times x

but:

2x = 2 times x
3x = 3 times x

Collecting and displaying data

This link explains how you might take a survey.

This link suggests ways of displaying data collected in a survey.

And this tool allows you to make your own graphs!