Stage: 3 Challenge Level: 
Thinking about rectangles and cuboids might be useful.
Try some numbers out for yourself.
Try some numbers out for yourself.
smartphone. Visualising. Index notation/Indices. Generalising. Number - generally. Mathematical reasoning & proof. Maximise/minimise/optimise. Creating expressions/formulae. Calculators. Working systematically.
Published November 1996,September 2008.
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