As a student, I really hated math. I wasn't good at it, didn't understand it most of the time, got confused by the formulas.
Imagine my dismay when I began weaving and discovered that I was going to need to use formulas and math!
There was a difference with this math, however. It wasn't theoretical, it had a purpose. And if I plugged the numbers into the formula, I got a meaningful answer.
(That's not to say I always did the formula correctly!)
So often new weavers will ask me how much yarn they need for a project. I tell them they have to do the math...
There are all sorts of places to find out what values to assign to the formula. If it is a simple "how much yarn do I need?" the formula is in most books and on-line spreadsheets. Marg Coe's Mother of All Spreadsheets can be found at her website and I think on Weavolution. It may be elsewhere, too, as she has very generously allowed it to be published.
When I started weaving it was books or magazines or nothing. There was no internet - at least not for the general public. Interweave Press published a little booklet sometime in the 80's, I think, with tables of use for weavers. It has things like recommendations for density for various yarns. I don't agree with all of them, but that's just me. Weavers will have to learn for themselves if what is being recommended is actually useful for the quality of cloth they want to make. Sample, sample, sample!
I still don't much like math - I think I have mild numerical dyslexia because I so often flip numbers when I'm punching them into the calculator. I can run the same formula three times and quite often get three different answers. :( But using a calculator is still better than trying to do it in my head!
So when new weavers ask how much yarn is needed for a project? I will help them do the math. But doing the math is what has to happen. Math phobe or not.