Stage: 4 and 5 Challenge Level: 
The scale at the side tells you how you're doing.
Make sure you can justify the order that the scale shows to be correct.
Generalising. Interactivities. Patterned numbers. Golden ratio. Manipulating algebraic expressions/formulae. Stage 5 - Reviewed 2012. Mathematical reasoning & proof. Number theory. Quadratic equations. Inequality/inequalities.
Published May 2001.
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