I would suggest doing the PATS course in Melbourne (
www.******************) . Virtually everyone hired by Jetstar and Qantas this year have done this course .
A few friends who were applying for CX did a one day individual course ,and the PATS instructors know pretty much every question that is on the Cathay maths test( more than 60% are failing this component - from friend who was told this by CX at his groundschool). My friends said they had seen every question before.