Hi ashszn,
You ask a really good question. Since you have been studying for some time and still struggle when answering GMAT quant questions, you really need to look at HOW you have been preparing for GMAT quant and make some changes, right?
Keep in mind that there is a significant difference between answering GMAT quant questions in a timed and pressure-filled environment and answering those questions with no pressure (after the fact). Thus, in order to improve your accuracy at correctly answering GMAT quant questions the first time you see them, you must improve your quant skills. To do so, I recommend following a structured study plan in which you individually learn each topic, and then practice each topic until you've gained mastery. By studying in such a way, you will not only develop sound skills in solving GMAT questions but also fill in gaps in your quant knowledge.
For example, let’s say you are learning about Number Properties. First, you should develop as much conceptual knowledge about Number Properties as possible. In other words, your goal will be to completely understand properties of factorials, perfect squares, quadratic patterns, LCM, GCF, units digit patterns, divisibility, and remainders, to name a few concepts. After carefully reviewing the conceptual underpinnings of how to answer Number Properties questions, practice by answering 50 or more questions just from Number Properties. When you do dozens of questions of the same type one after the other, you learn just what it takes to get questions of that type correct consistently. If you aren't getting close to 90 percent of questions of a certain type correct, go back and seek to better understand how that type of question works, and then do more questions of that type until you get to around at least 90 percent accuracy in your training. If you get 100 percent of some sets correct, even better. Number Properties is just one example; follow this process for all quant topics.
When you are working on learning to answer questions of a particular type, start off taking your time, and then seek to speed up as you get more comfortable answering questions of that type. As you do such practice, do a thorough analysis of each question that you don't get right. If you got a remainder question wrong, ask yourself why. Did you make a careless mistake? Did you not properly apply the remainder formula? Was there a concept you did not understand in the question? By carefully analyzing your mistakes, you will be able to efficiently fix your weaknesses and in turn improve your GMAT quant skills.
So, work on accuracy and generally finding correct answers, work on specific weaker areas one by one to make them strong areas, and when you take a practice GMAT or the real thing, take all the time per question available to do your absolute best to get right answers consistently. The GMAT is essentially a game of seeing how many right answers you can get in the time allotted. Approach the test with that conception in mind, and focus intently on the question in front of you with one goal in mind: getting a CORRECT answer.
In order to follow the path described above, you may need some new quant materials, so take a look at the GMAT Club reviews for the
best quant courses.
You also may find it helpful to read the following articles about
how to increase your GMAT quant score and
the phases of preparing for the GMAT.
If you have any questions, feel to reach back out. Good luck!