Question

Khianna says that she found a shortcut to calculate the surface area to volume ratio.

Answer 1

The process works well for a cylinder. It will not work for any other 3-D figures.

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I haven't needed to use a method, so there is no comparison.

If you are asked to find the area and volume, then the area/volume ratio, usually you will do it in that order. The "shortcut" is only useful if you don't need either volume or surface area as part of the answer to the question.