I know how you feel.
It's been 3+ years since I've even looked at a math problem, and I was worried that I might not score well enough in the two math areas. I took the practice test on military.com and didn't do as well as I wanted to in Mathematics Knowledge.
military.com Full-Length Test 1 results:
General Science - 18 Correct, 7 Incorrect, 72 Correct %
Arithmetic Reasoning - 26 Correct, 4 Incorrect, 86.7 Correct %
Word Knowledge - 30 Correct, 5 Incorrect, 85.7 Correct %
Paragraph Comprehension- 14 Correct, 1 Incorrect, 93.3 Correct %
Auto & Shop Information - 13 Correct, 12 Incorrect, 52 Correct %
Mathematics Knowledge - 13 Correct, 12 Incorrect, 52 Correct %
Mechanical Comprehension - 10 Correct, 15 Incorrect, 40 Correct %
Electronics Information - 7 Correct, 13 Incorrect, 35 Correct %
I wanted to score well in the ST Line Score for the job I want to get into.
http://www.military.com/ASVAB/0,,ASVAB_MOS_Army.html
ST - Skilled Technical: GS+VE+MK+MC
...The ASVAB subtests are: General Science (GS); Arithmetic Reasoning (AR); Word Knowledge (WK); Paragraph Comprehension (PC); Numerical Operations (NO); Coding Speed (CS); Auto and Shop Information (AS); Mathematics Knowledge (MK); Mechanical Comprehension (MC); Electronics Information (EI); and Sum of Word Knowledge and Paragraph Comprehension (VE). Note that as Numerical Operations (NO) and Coding Speed (CS) subtests are phased out, some line scores may be changed...
So the day that I went to take the ASVAB I was a little worried about scoring well enough that I didn't have to retake the test.
The actual test was way easier than the practice test!!!
I scored a 92. I don't know my Line Scores yet, but they should be good.
http://usmilitary.about.com/od/joiningthemilitary/l/blafqtscore.htm
I used a couple of ASVAB books to review information and practice some of the questions; I took the practice tests online; studied a bit at march2success.com; and checked out a math tutor video at the library. The ASVAB ended up being much easier than I expected.
I wish you luck.