An 80th percentile GMAT quant score is said to be necessary to get admitted to many of the top MBA programs in the U.S. Is this true? Who knows? I went to the Kellogg School of Management, but scored below the 80th percentile on GMAT quant. That said, it certainly helps and is an excellent GMAT score goal. Do you want to score above the 80th percentile on GMAT quant?
The most important GMAT quant skills are built with practice, not granted at birth. It’s important to remember that the GMAT is not a test of your mathematical knowledge in an academic sense; it tests your ability to efficiently handle mathematical data to make decisions. In fact, the GMAT only really tests math concepts up to the high school level, with some basic additional probability and combinatorics topics sprinkled in. But there is no pre-calculus and certainly no calculus on the GMAT.
The following topics are included in the GMAT quant section: Arithmetic, Word problems, Number properties, Algebra, Sets, Probability, Statistics, Combination and Permutation, and Geometry. Though the GMAT does not test mathematical concepts beyond the high-school level, it’s the application of basic concepts in the limited time that makes things interesting and tricky.
To score above the 80th percentile on GMAT quant, you’ll need to efficiently solve 31 questions in 62 minutes. Merely getting the correct answer won’t help if it takes you too long, as you have on average only two minutes per question. This makes it imperative to apply an efficient approach to each GMAT quant question.
In this article, we’ll explore five GMAT skills that can make the difference between an average GMAT score and a 90th percentile GMAT quant score (or better). These are skills anyone can build, and they don’t involve hundreds of hours of math practice. In fact, many people who believe they are quite good at math tend to struggle on GMAT quant without substantial practice. The GMAT quant section demands critical thinking, strategy, and problem solving.
Let’s talk about the must-have skills to ace the GMAT Quant section.
If you do not love math, that’s going to be fine. Liking math is not a prerequisite to perform well on the math section of the GMAT. But, being ready to engage with and have confidence with math is important. It is possible that over a period of time, you might have forgotten some formulas. So, you must be in a state of mind to recollect them. But, once you recall some simple formulas, questions that seem quite difficult become much easier.
That said, is mastering the application of math formulas to understand how to crack the GMAT quant section? The answer is No.
In high school and college, you were probably able to solve math problems by applying linear thinking. The objective in school is often to acquire math knowledge, not necessarily build math aptitude. There was less emphasis on how a particular question could be solved in multiple ways. For example, you must have learned that if you deal with three variables, in order to find out the values of the variables, you need three equations. However, if you are myopic with this particular thought process, you may lose valuable time and obtain a lower score on the GMAT.
Let’s take a typical GMAT Data Sufficiency question to understand this better.
What is the cost of 4 toffees and 7 candies?
Solution:
So we are dealing with the cost of a cookie, the cost of a toffee, and the cost of a piece of candy. Yes, there are three variables. We are asked to find the cost of 4 toffees and 7 candies. The traditional way of dealing with the question is by getting the cost of a toffee and the cost of a candy. However, since there are only two linear equations (from the two statements) for the three variables, we do not seem to get the value of the cost of a toffee and the cost of a candy.
Is E therefore the correct answer? Not necessarily. Here, the GMAT tests your thinking from another perspective. Is it necessary to get the cost of a toffee and the cost of a candy to get the cost of 4 toffees and 7 candies? The answer is No.
Let’s discuss this in more detail.
Statement 1 tells us the cost of a particular combination of toffees, candies, and cookies. Clearly, we cannot extract the cost of 4 toffees and 7 candies from this statement, alone. So, Statement 1 alone is insufficient.
The same is true for Statement 2. Thus, Statement 2 alone is insufficient, too.
Together, we will have two equations with three variables. First of all, the two equations are distinct, i.e. the second equation CANNOT be obtained by multiplying or dividing the first equation by a number. However, we know that to get the values of the three variables (out of which, the values of two variables we want to answer the question), we need three equations. In general, to get the values of variables, we need equations.
So, are both statements together insufficient?
Actually, no.
In the equation, we are asked for the value of 4 toffees and 7 candies. The question doesn’t talk about the cost of cookies. So, let’s try to eliminate cookies from these two equations.
To represent the statements in equation form, let’s say is the cost of a toffee, is the cost of a candy, and is the cost of a cookie.
Now, from two statements, we have two equations.
….(1)
….(2)
Since in the question, we are looking for a value of , let’s try to eliminate from these equations. To eliminate , let’s multiply equation (1) by 2 and then subtract it from the second equation. We’ll have
Simplifying it, we have
Okay! This is what we were looking for in the question. So, we have the value of . And since the value is unique, the statements together are sufficient. Therefore, the answer is option C.
In this question, we observed that even though there were fewer equations than variables, a unique answer still existed. So, you shouldn’t discard a set of linear equations only because the number of variables is greater than the number of equations. You should try to manipulate the equations to see if what we want can be found.
Two equations in two variables don’t necessarily mean that a unique solution is possible.
Let’s explore strategies for another GMAT data sufficiency question to understand this.
What is the cost of a banana?
Solution:
Having gone through the first question, this one would seem to be an easier one. Because there are two linear equations and two variables, one can be confident in obtaining the value of each variable, right?
Not really. Let’s discuss further.
Clearly, each statement alone is insufficient since each statement involves two variables, and the question asks us to find the value of one variable (i.e., the cost of a banana.)
What if we combined both statements?
Then, we’ll have two equations in two variables. Conceptually, we know that a unique solution can be achieved if we have two linear equations in two variables. So, let’s try solving the two equations and finding the value of the variables.
Let’s denote the cost of a banana by and the cost of a mango by . The linear equations for both statements are:
Now, let’s try to solve the equations.
Let’s try eliminating from the two equations since we want the value of . So, let’s multiply the first equation by so that we get i.e., the co-efficient of in the second equation.
Multiplying equation (1) by , we get
…(3)
We can notice that equation (3) is exactly the same as equation (2). So, if we subtract it from equation (2) to eliminate , everything gets eliminated, and we get . We see that we cannot find a value of (or even ) from these equations.
Why?
The reason is that these equations are not really different equations; they are essentially the same equation disguised in different forms. We know that in an equation, we can multiply or divide all the components by a number without affecting equality. We can notice that Statement 2 is, in fact, Statement 1, multiplied by .
So, we see that when one equation is just a different version of another equation (i.e., we can multiply or divide one equation by a number to get another equation), then we cannot find a unique solution to a set of two variables from two equations. The same is also true for equations in . We require all the equations to be distinct if we want to find a unique solution for variables.
So, before making any judgment on a set of equations about sufficiency, always check whether one of the equations is not a multiple of the other. Don’t make unwarranted assumptions. The answer is Option E.
Simply solving a greater number of questions does not guarantee that you will learn how to improve your GMAT quant score.
If you are doing a lot of GMAT practice problems, but consistently getting certain types of problems wrong (i.e., you are struggling with data sufficiency questions in general, or aren’t understanding the probability concepts being test, etc.), you are probably not on a path to improving your GMAT quant score. You may want to work with an online GMAT tutor who can explain what you are doing wrong and help you course correct. Too many students fall into what is called the “illusion of competence” whereby they get a problem wrong, read about how to do it correctly, and then assume they know it. If you are keeping a GMAT error log, however, you’ll soon realize that you don’t truly understand certain types of question.
You need to follow the tenants of deliberate practice to learn how to study more effectively when engaging in GMAT prep.
These include:
To maximize improve your quant score on the GMAT, study deliberately. Don’t just do practice GMAT problems over and over again.
Earlier on in your GMAT study efforts, strive for accuracy and forget about the time. Do not put yourself under time constraints right away. There is no point in completing 31 questions in 62 minutes if15 are wrong. The GMAT quant score would be low.
First, focus on doing questions correctly and then think of speed. It is important to analyze your correct as well as incorrect questions. You must analyse your correct answers because there may have been a faster way to get the problem correct.
That said, timing matters a lot on the GMAT. The key to a high GMAT quant score is to get the questions correct in a limited time. So, first, you must focus on developing the conceptual knowledge, but then you must extent to developing an approach to answer questions quickly. If you are studying for the GMAT but not doing so under time pressure, you may actually be harming your score at some point. You could be building habits that result in it taking you too long to solve the problems. Timing on the GMAT is crucial.
Try to think from the test-makers’ perspective. Why did the test-maker make the question like this? What could be another way of solving the question?
Five keys for understanding how to improve your GMAT quant score are:
1. Have strong proficiency in high school math, but not necessarily that much more!
2. Lear how to analyze GMAT quant questions from multiple perspectives
3. Limit the use of assumptions
4. Practice deliberately, not just more
5. Focus on accuracy initially, but recognize the importance of speed
If you are looking for a GMAT tutor online or for GMAT tutors in Chicago or other major cities like Boston or New York, we can help. We help students build customized study plans and understand how to apply the above concepts to learn how to improve their scores on the GMAT quant section.