PHP -- Runescape Calculator?

I need a little help making a Runescape Calculator with php...
All I need to do is:
*Take the current XP
*Subtract
*Then show the data

I'm just beginning PHP, so any help would be teriffic!

 

What your asking is quite trivial at best and after one day of studying PHP, you should know how to do this yourself. So let me suggest this:
http://www.w3schools.com/php/php_intro.asp

If you seriously try to learn and still have troubles, come back with a more detailed explanation that answers these questions:
Take the current EXP from where?
Subtract what?