haha, I had that. You have to get 60%. I think i managed about 10%. If you fail, you have to take a Maths Unit. Its mainly A level maths, I only managed a B for GCSE. I hadn't done maths since school when I took my test.
Logs, Ven diagrams, hexadecimal, octal, Sum Ofs (with all those Greek letters) etc. Don't worry about it too much. I managed to pass the test in January with 72%. They teach it really well and make it very easy to understand.