I find it helpful to just explore the areas of math that "stand in the way" when I am studying something practical. After all, math is rarely a target, math is a language that you use to solve a problem.

Sometimes a wikipedia article (along with sources at the bottom) is enough, sometimes I'd need to buy a book, like in case with statistics. Amazon book reviews are usually very helpful and good math books are quite expensive (easily in $100+ range) but can be had for a fraction of original price when bought used.