Modelling Scales

Someone help me out here...

If a model is 1/72, then presumably the appropriate figure size is 25mm.

(unless my maths is significantly lacking)

However generally speaking manufacturers link 1/72 with 20mm.

What is the deal with that?
*grin*

Really what I want to know is how compatible are 1/72 vehicles with 25mm

(say Stargrunt) figures

Thanks
Donogh

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