Hi gmarius,
These days, the 60th percentile in the Quant section is right around a Q44 - but I would be surprised if that's an actual GMAT-based "requirement" that those Schools require (or if it's the ONLY one). As such, I have to ask why that is one of your specific goals. Did a representative from one of those Programs explicitly state that that score was a requirement to apply?
While you don't have to be a 'math genius' to score a Q44, you do have to have a certain proficiency in basic math (meaning that you have to know all of the necessary formulas/rules and you have to be able to do math by hand without making little mistakes). Beyond those skills, you would likely also benefit a great deal by learning/practicing certain Quant Tactics that would help you to answer questions in efficient ways (and avoid the questions that don't matter to your score). Based on your prior GMAT performance, all of that work will likely take some time - at least another 2-3 months of consistent, guided study.
You might need to take a short 'detour' from your GMAT studies to work on your math 'skills.' For free math practice and help, I recommend that you set up an account at Khan Academy (
www.khanacademy.org). The site is completely free and makes the learning a bit more fun and 'game-like' (as opposed to the dry academic approach taken by most books). While the site is vast, you should limit your studies to basic Arithmetic, Algebra and Geometry. After spending a little time re-building those skills, you can restart your GMAT studies.
If you have any additional questions, then just let me know (and you can feel free to contact me directly).
GMAT assassins aren't born, they're made,
Rich