Android multiple screen sizes with same density

Question

I\'m confused regarding the densities. I see that with medium density, the screen resolution could be either 320x480, 480x800, or 480x854. So if I have an image thats 300px

Answer 1

So if I have an image thats 300px wide in the mdpi folder, how is it going to look the same size on all 3 different screen sizes (mainly 320x480 vs the other 2)?

How the image looks, physically, is driven by screen density, not screen size. Your -mdpi folder is not tied to screen size -- it is tied to screen density.