Skill Gem Math Calculation?

Hi, I noticed my gems calculation seem to be off. For example the shockwave on boneshatter has a base aoe of 2 meters. When I add magnified effect to it, it becomes 2.4 meters. Magnified effect says 40% more aoe. It was my understanding that more means multiplicitive and increased means additive. 40% of 2 is 0.8 so why is the aoe range 2.4 and not 2.8? Thanks for any help.

Have you calculated the actual area?
After all, the function for that is pi*radius².
In this case, 3.14*4 = 12.56, and 3.14*2.36² = 17.5.
I assume that's what it is, they switched from radius to area in PoE 1 a few years ago.

So how do I convert it to the numbers ingame? It just says range 2.4 after adding the gem not 17.5. Its been a long time since ive done math like this but im interested in learning and understanding the game more. Thanks for the help.

The area modifiers increase the actual area.
The radius in meters is the number that is shown.

The area of an effect is pi * radius * radius. For ease of calculation, pi is usually assumed as 3.14.

So the 12.5 or 17.5 is the amount of square meters, while the radius is the distance from the point of origin, f.Ex. the centre of an explosion.

so that 2 meters is diameter i guess but to make math simple we'll says radius, it wont mater to the scale in these small numbers. Radius is half the diameter. the area of a circle is pi*r^2 in this case the base area is pi*2^2=12.56. we'll say 12.5 for easy math. 12.5 increased 40%(12.5*1.4)=17.5.
17.5 is the new area. so pi*r^2=17.5 formula for radius based on given area is
r = √(A / pi). √(17.5/ 3.14)=2.36. The area is increased by 40%. If you don't wanna deal with square roots. https://www.omnicalculator.com/math/area-of-a-circle

Ok I understand how it works now that makes sense. Thanks for the help and math lesson guys.