I got a VServer with 8GB Ram and 4 cores, how many Minecraft servers do you think I could install on it?
Basically: infinite. I myself have a smaller V-Server with just 2 V-Cores and 2 GB RAM and even running 4 Minecraft Servers + Proxy without any problems. If you gave each server a maximum of 1 GB, you could have 6-7 servers running at the same time (+ proxy).
Okay, thanks for the helpful answer!
Depends on the version, how many players, how many plugins, etc.
Let's assume it's version 1.8.9 and the server has 20 slots with 10 plugins.