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Peeling the Apple or the Cone That Lost Its Head

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Stage: 4 Challenge Level: Challenge Level:3 Challenge Level:3 Challenge Level:3

As an example of how you might begin, take one litre as the volume.

How many cubic centimetres is that ?

If the radius was 1 cm, 2 cm, 3 cm, etc. what would the height be each time ?

And how long would the 'slope length' be in each case ?

How do you calculate the curved surface area using those things ?

When was the curved surface area least ?

Can you refine your answer with more precise values tried for the radius length ?

Could a spreadsheet help with the repeated calculation ?