I am fortunate enough to have a mind that calculates numbers well but if you don't use numbers to play WGT or real golf, you won't be successful.
There is a built in calculator on virtually every computer, just pop it up on the screen if you aren't good at math in your head. Also I use Maxthon as my browser and it has a really good notepad that I use from time to time to help with specific shots on specific courses, so you know when a hole plays long, etc.
Tools like this can really help.