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## 'Cola Can' printed from http://nrich.maths.org/

*This printable worksheet may be useful: Cola Can.*

Once the lower level thinking covered in the Hint has been assimilated students might be guided if necessary to see the value of a spreadsheet when solving a problem of this sort.

Additionally the use of a graph representing the spreadsheet values is particularly helpful for 'picturing' the behaviour of the surface area function as either base radius or can height varies.

There is a valuable opportunity to work with each of the two obvious independent variables : base radius and height. Starting with either of these the other is calculable from the specified volume of 330 ml, and once both r and h are known the surface area is calculable.