The three numbers correspond to (a) the average mark of all applicants (b) the average mark of shortlisted applicants and (c) the average mark of successful applicants. 2013 is a toughie!
The Maths Aptitude test is used by Oxford and Imperial universities as part of their admissions process. Here is a bare bones syllabus for the MAT provided by Oxford: Syllabus
Worksheets for practising certain topic-based skills for the Maths Aptitude Test, particularly for Section A.
Advice on answers Section B questions on the Maths Aptitude Test.
Lots of past paper questions with solutions and tips, divided up by topic.
I produced these the evening students took the 2015 paper! (after a Tiffin student requested them)