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By the way, about ISAT, it's actually totally different from SAT. SAT assesses one's aptitude in maths, english, science etc among others. On the other hand, ISAT is basically a modified IQ test. They will have questions like, "if all cats are tame, and some cats are black, then all tame cats are black - right or wrong?". There is also a "comprehension" component where you are presented with a graph and you have to interpret it. There are also some metaphorical stuff - the one I remember the most is, there is a guy's sillhoeutte with finger prints overlying the sillhoeutte, and the question is asking you to choose an appropriate interpretation of that picture out of four options.
ISAT is not too hard, in fact it's possible to score 100 in it. On the other hand, it could be challenging in that some medical schools in Australia (Western Australia, if I'm not mistaken) requires a pretty high ISAT score (something like >90 for two components) as one of the prerequisites for admission. But there's actually nothing much one could prepare for it. Just make sure that you enter the exam hall fresh and alert, and you will do well.
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