If you don't understand the concepts at all of general maths then you should get a tutor so they can explain it to you so you actually understand what your doing. However, if you know the basics and just make mistakes in the exams, or have trouble with questions that are unfamiliar to you in the actual exams then get the excel/success one books which have past papers and sample questions in so you can practice (over and over again) questions which may be a little different to the ones in your textbook. Having said that, I've never had a tutor but I guess they would get past papers for you. It really just depends on how much your struggling.
About that computer tutor thing, isn't it one program which can help with maths from K-12?? So unless you have younger brothers/sisters its probably a waste of money because you've only got 2 terms left anyway..