How to prep for math?

<p>I am contemplating retaking my ACT in order to improve my math score. To be honest, I don't care if my composite score improves (31) but I got a 25 in math that's really upsetting me. So how do you prep for math? Which is the best book to buy? I've taken math through pre-Calc and haven't done horrendously but it does take me a bit longer to comprehend concepts.</p>