As itas title suggests, the equivalency is based on GCSE maths. The organisation that is setting the test should provide you with topic areas to study in advance. Contact the them and ask for a syllabus. You can also look at past GCSE maths papers by looking at the various exam boards and GCSE maths revision guides will help you work out the main areas you need to cover.
James
Have a look at the TDA website for practice tests. Base your study on this styleof question. Your Uni library (if you're at Uni) should have books to help
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