How simple algebra can be used to investigate cubes and other polyhedra up to icosahedra.
Mutiplying and dividing fractions: a systematic approach to this perennial problem.
Harry gives an introduction to the difficulty of writing large numbers in Roman Numerals
Making life easy when using percentages. A sometimes fraught topic looked at differently.
Bill introduces queueing theory and uses it to design the most efficient check out line
Be wary of high interest rates! An introduction to how loans grow.
A pen and pencil method of extracting square roots
A better way to extract square roots, with rapid convergence