[Teddy]

Well the clue is the "extract" part of the label.

Please read more about this before taking supplements, it is fairly standard stuff for herbs, as a mistake could mean taking a lot more or less than you wanted to take.

Basically, your RR is an extract (some sort of chemical process that takes the raw ingredient, gets rid of anything that's not useful, and then packages that into the product).

So, that's 2500mg raw RR, that went through some sort of processing, to fit the "desired" or "active" components into a 500mg capsule.
5:1 extract of 500mg.  500mg * 5 is 2500mg.

In principle, yes. 

However, the extraction method and solvent have a great impact what is extracted and what is left behind. Therefore, in general, extract may lack some of the useful stuff, either because they are soluble to the solvent used (often either water or alcohol), or the method might use such a high temperature that some of substances are changed/destroyed.

In the other hand, in some cases the extract is utilized/absorbed either better or, sometimes, less well than the raw material.

That makes it very difficult to judge the real effective extraction ratio, and also to compare different suppliers' products. It is a bit frustrating situation. I am myself therefore using RR and PM in natural powder format, mixing it in a suitable smoothie-type drink.