Stage: 5 Short Challenge Level: 
Don't overcomplicate things: Some of the parts of the problem are very simple!
For the trickier parts you will only need pythagoras and basic trigonometry.
Don't forget to think about the result!
AM/GM inequality. Mathematical reasoning & proof. Geometric mean. Stage 5 - Reviewed 2012. epsilons. Visualising. Real world. Harmonic mean. Inequality/inequalities. Working systematically.
Published October 2009.
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