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To be honest, I would not read too much into your test. Remember, you are dealing with a small sample size of only 31 quant and 36 verbal questions. The main takeaways are that you need to improve your Sentence Correction and Critical Reasoning skills, and also fill in quant knowledge gaps. As for how to improve those skills, let’s start with Critical Reasoning.
To improve in Critical Reasoning, you first need to master the individual topics: Strengthen the Argument, Weaken the Argument, Resolve the Paradox, etc. As you learn about each question type, do focused practice so you can track your skill in answering each type. If, for example, you get a weakening question wrong, ask yourself why. Did you make a careless mistake? Did you not recognize the specific question type? Were you doing too much analysis in your head? Did you skip over a keyword in an answer choice? You must thoroughly analyze your mistakes and seek to turn weaknesses into strengths by focusing on the question types you dread seeing and the questions you take a long time to answer correctly.
Another major mistake that people make when training for CR is that they do practice questions too fast. To get Critical Reasoning questions correct, you have to see exactly what's going on in the passages and answer choices, and you likely won't learn to do so by spending a few minutes on each question. At this stage of your training, you may need to spend even fifteen minutes on each question, learning to see what there is to see. Here is a way to look at this process: If you get a new job in a field in which you are not experienced, you may not be as fast as the other people working with you, but you know you have a job to do and you make sure you learn all the angles, so that you do the job well, if not as quickly as those around you. Rushing through the job and doing it incorrectly would not make sense. Then, as you gain more experience, you learn to do the same job more quickly. Think of Critical Reasoning questions similarly. Your job is to do what? To get through questions quickly? Not really. Your job is to get correct answers.
So, first you have to learn to get correct answers, generally at least 10 to 15 in a row consistently, and more in a row would be better. That is your job, and if it takes you 15 minutes per question to get correct answers consistently, then so be it. Only after you have learned to get correct answers consistently can you work on speeding up. Working quickly but not doing your job is useless. Better to work slowly and learn to do your job well. You can be sure that with experience, you will learn to speed up, and then you still will be doing your job well, i.e., getting correct answers consistently.
Regarding Sentence Correction, there are three aspects to getting correct answers to GMAT Sentence Correction questions: what you know, such as grammar rules, what you see, such as violations of grammar rules and the logic of sentence structure, and what you do, such as carefully considering each answer choice in the context of the non-underlined portion of the sentence. To drive up your Sentence Correction score, you likely will have to work on all three of those aspects. Furthermore, the reason that your Sentence Correction performance has not improved likely is that you have not been working on all three of those aspects.
Regarding what you know, to be successful in Sentence Correction, first and foremost, you MUST know your grammar rules. Let's be clear, though: GMAT Sentence Correction is not just a test of knowledge of grammar rules. The reason for learning grammar rules is so that you can determine what sentences convey and whether sentences are well-constructed. In fact, in many cases, incorrect answers to Sentence Correction questions are grammatically flawless. Thus, often your task is to use your knowledge of grammar rules to determine which answer choice creates the most logical sentence meaning and structure.
This determination of whether sentences are well-constructed and logical is the second aspect of finding correct answers to Sentence Correction questions, what you see. To develop this skill, you probably have to slow way down. You won't develop this skill by spending under two minutes per question. For a while, anyway, you have to spend time with each question, maybe even ten or fifteen minutes on one question sometimes, analyzing every answer choice until you see the details that you have to see in order to choose the correct answer. As you go through the answer choices, consider the meaning conveyed by each version of the sentence. Does the meaning make sense? Even if you can tell what the version is SUPPOSED to convey, does the version really convey that meaning? Is there a verb to go with the subject? Do all pronouns clearly refer to nouns? By slowing way down and looking for these details, you learn to see what you have to see in order to clearly understand which answer to a Sentence Correction question is correct.
There is only one correct answer to any Sentence Correction question, there are clear reasons why that choice is correct and the others are not, and those reasons are not that the correct version simply "sounds right." In fact, the correct version often sounds a little off at first. That correct answers may sound a little off is not surprising. If the correct answer were always the one that sounded right, then most people most of the time would get Sentence Correction questions correct, without really knowing why the wrong answers were wrong and the correct answers were correct. So, you have to go beyond choosing what "sounds right" and learn to clearly see the logical reasons why one choice is better than all of the others.
As for the third aspect of getting Sentence Correction questions correct, what you do, the main thing you have to do is be very careful. You have to make sure that you are truly considering the structures of sentences and the meanings conveyed rather than allowing yourself to be tricked into choosing trap answers that sound right but don't convey logical meanings. You also have to make sure that you put some real energy into finding the correct answers. Finding the correct answer may take bouncing from choice to choice repeatedly until you start to see the differences between the choices that make all choices wrong except for one. Often, when you first look at the choices, only one or two seem obviously incorrect. Getting the right answers takes a certain work ethic. You have to take the time to see the differences and to figure out the precise reasons that one choice is correct.
To improve what you do when you answer Sentence Correction questions, seek to become aware of how you are going about answering them. Are you being careful and looking for logic and details, or are you quickly eliminating choices that sound a little off and then choosing the best of the rest? If you choose an incorrect answer, consider what you did that resulted in your arriving at that answer and what you could do differently in order to arrive at correct answers more consistently. Furthermore, see how many questions you can get correct in a row as you practice. If you break your streak by missing one, consider what you could have done differently to extend your streak.
Although your quant is stronger than your verbal, to improve your quant score to a 48+ level, you’ll need to engage in topical, focused practice. For example, if you are reviewing Number Properties, be sure that you practice 50 or more questions just from Number Properties: LCM, GCF, units digit patterns, divisibility, remainders, etc. 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. Number Properties is just one example; follow this process for all quant topics.
Each time you strengthen your understanding of a topic and your skill in answering questions of a particular type, you increase your odds of hitting your score goal. You know that there are types of questions that you are happy to see, types that you would rather not see, and types that you take a long time to answer correctly. Learn to more effectively answer the types of questions that you would rather not see, and make them into your favorite types. Learn to correctly answer in two minutes or less questions that you currently take five minutes to answer. By finding, say, a dozen weaker quant areas and turning them into strong areas, you will make great progress toward hitting your quant score goal. If a dozen areas turn out not to be enough, strengthen some more areas.
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 verbal and quant materials, so take a look at the GMAT Club reviews for the
best verbal and
quant courses.
Feel free to reach out with any further questions.