It depends on your background, wether you are a native or not etc... It is very difficult to quantify this, so I will only give you indication based on what friends of mine have been doing, and what I read on the forum.
However, I would suggest around 3 months of study, with 3 to 4 hours a day of study on average (you can spend more time on week ends)
- the quant part might be the easiest to improve, so you can spend a couple of weeks on it.
- The verbal is not that bad for you, 33 is a good start. Try to diagnose where you need improvement. It is however the part where it is difficult to improve in my opinion, so try to keep that in mind.
Let me know what your diagnosis is (strength and weaknessed depending on the question type) for both Q and V, and I'll try to give you additional infos.
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