Subject: How is Jupiter's core 30,000 degrees Celsius.How do I calculate that myself

I was looking at The compact NASA Atlas of the Solar System [Ronald Greeley & 
Rayond Batson, Cambridge press. 523.2 GRE], and it says that Jupiters core is 
thirty thousand degrees Celcius. I understand why temperature increases with 
pressure, atomically, but I'm having trouble finding the mathematical 
realationship for this. When I try to rearrange the gas law formula to figure 
out how NASA got a core temperature of 30,000 degrees Celsius I got something 
less than half that. If I were to take the mass of Jupiter and that temperature 
I could get a ratio but I doubt that it is a linear relationship. Can you 
explain the math that allows us to know how 30,000 degrees Celsius is the core 
temperature for Jupiter, how it was calculated, assuming 100% Hydrogen (which I 
know it isn't) for simplicity, so that I can apply this formula to any mass gas 
giant to get a rough idea of core and surface temperatures.  Thanks.

Re: How is Jupiter's core 30,000 degrees Celsius.How do I calculate that myself