[FMX04] Calculate scale...maths experts required!

This is probably going to be a really easy question for you guys but my maths is a bit flakey.:frowning:

I need to calculate a scale factor (nothing to do with perspective). I’m working on a project that involves users increasing and decreasing the size of an image loaded into an MC. I’d like to know by what amount the image has been increased or descreased expressed as a percentage or decimal.

Cheers