Stage: 3 and 4 Challenge Level: 
See the Teachers' Notes to Arithmagons
for a possible approach to working with an essentially
identical problem.
Making and proving conjectures. Generalising. Manipulating algebraic expressions/formulae. Stage 5 - Reviewed 2012. Creating expressions/formulae. Inequality/inequalities. Trial and improvement. Polynomials. Stage 5 needs dealing with. Mathematical reasoning & proof.
Published December 2002.
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