there is no set passmark, it is an assessment of your PULHHEEMS mate (Physical, Upper, Lower, Hearing left, Hearing right, Eyesight left, Eyesight right, Medical and strength) (correct me if i am wrong on any of them by the way please) it is recommended that you wear a full suit as it shows the OC there that you are a smart and well presented potential soldier which goes without saying is a good start.
Just give it your all and show that you are keen and confident and you will do well mate.
Id recommend a suit mate, its not essential but shows you could be bothered, as well as that id work on the little things as well, Try to maintain eye contact, speak with confidence and as MSI64 said make sure your shoes are shiny
Didn't you get the sheet on how to prepare for the interview? You'll have to know about you 3 job choices, what training they do and where and for how long and what you will do at training Phase 1 and Phase 2. Know a bit about the corps/regiments history. Know the policy on drugs, tattoos and body piercing, know some vehicles or equipment you may have to use in your job choices, brush up on current army operations and deployment, what role the army has, not just defence and why you want to join the army and the jobs you've chosen, the other questions you can think of on the spot, these need a little revision.
Yes I've had the interview, I was also given the sheet, however none of what was on the sheet was covered, besides knowing what 3 job choices you want, I think its for your own benefit to know those things, and they will be covered in the second interview I assume? unless it does happen on the first interview, though it didnt for me.
Taking that into consideration, that it went different for me but might not for everyone its good to know the details mentioned above.