RyanCJW is 100% correct: the important thing on the quant section is to get a sense of what two minutes feels like, and you definitely need to learn to let go of questions. If you don't see a clear path to the solution within a minute or two, just guess and move on. There's absolutely no point in spending five minutes chasing a question that you don't completely understand--that's a good way to get yourself into all sorts of trouble on the quant section.
On integrated reasoning, I think the best strategy is to conserve energy, and focus only on the questions that are relatively comfortable for you. If you're stronger with the data tables, for example, you might consider putting more energy into those, and maybe you would skip the algebraic questions or the wordier IR questions that resemble critical reasoning. Most MBA programs aren't putting much emphasis on the IR section yet, so there's no reason to rupture brain cells on that section. It's not adaptive either, so just skip the ones that give you trouble, and try to be accurate on the IR question types that you're comfortable with. As long as you fall somewhere close to the median score (currently 4.34 out of 8), you're probably fine.
Good luck, Harsh!
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