It depends on how good you are at math. I would say it's pretty darn easy, but I got a 31 on the ACT math without completing the whole test and math I'm very strong in math. If you ask someone very strong in English, but who got a 20 on they would probably consider it more difficult... I don't know what "number logic" is, but you're going to need to know algebra 1 and 2 as well as geometry. Trigonometry and statistics questions will show up on the ACT too, but not as much as your general first 3 year of high school math. Study those and get books more geared to ACT math. SAT math comes pretty close, but doesn't cover trig.
It's kind of hard but look over the basic formulas for math before you take your ACT and it's mostly on algebra, geometry and 3 or 4 question from trigonometry... I'm taking my ACT on this Saturday and I have not start studying for it yet but I will look over the formulas tomorrow so I will remember it.... GOOD LUCK!!!!