>>12240348If you can't do basic numeracy such as adding four digit numbers with pen and paper, making change for a dollar, dividing a takeout bill between four people or taking percentages, you might need some kind of remedial book or adult numeracy course. My first suggestion is that you can ask a librarian at your nearest library to help you find an adult numeracy book.
If you can manage that and want to catch on basic high school stuff, either work through Khan academy or the following books in order:
Algebra - I. Gelfand
Geometry - I. Gelfand
The Method of Coordinates - I. Gelfand
Functions and Graphs - I. Gelfand
Trigonometry - I. Gelfand
Precalculus - Stitz & Zeager
Basic Mathematics - Lang
Except for SZ (which is a free pdf from their site) these are all free on libgen. I'd suggest just doing the chapter tests in order to see where you are at and only start actually reading once you hit a wall. Additionally, this list is very redundant as the later Gelfand books cover a lot of the stuff that SZ and Lang cover. In theory you can ignore Gelfand entirely but it does a good job at hammering the basics in. I skimmed all of them before I went to university and it took 4 afternoons so if you're new I'd estimate a month of 1 hour a day to be confident.
All mathematics past that point is ultimately either for a specific career, a hobby or just for the sake of wanting to discover mathematics. An introductory statistics book is probably a good capstone if you want to stop at that point.
If you've got that far and want to continue, there are four ways to proceed. These are linear algebra, calculus, axiomatic geometry and competition math. The first two are required for going into advanced mathematics and make up the first year of an undergraduate degree while the latter two are just hobby fields of math with minimal real world uses but also minimal barriers to entry. When the time comes to consider these, either check the site in the sticky or make another thread here.
