Articles published in GRE Quant

More Fun with GRE Variables

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Manhattan Prep GRE Blog - More Fun with GRE Variables by Chelsey Cooley

You can attend the first session of any of our online or in-person GRE courses absolutely free. Crazy, right? Check out our upcoming courses here.


In my last blog post, we practiced using GRE variables to solve Quant word problems—and we solved some problems without using variables, too. The big takeaway: you don’t have to start every word problem with a tidy little list of variables and equations! It’s okay to focus on the numbers in the problem first. However, variables are sometimes the key ingredient to getting a GRE problem right. In this article, we’ll try using variables to solve some tougher GRE Quant word problems.

Here’s one of my favorite problems from the 5lb. Book of GRE Practice Problems. Give it a try before you keep reading: Read more

GRE Math for People Who Hate Math: Absolute Value

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Manhattan Prep GRE Blog - GRE Math for People Who Hate Math: Absolute Value by Chelsey Cooley

You can attend the first session of any of our online or in-person GRE courses absolutely free. Ready to take the plunge? Check out our upcoming courses here.


Think of an absolute value as a simple machine that looks like this: ||. You put a value into it, and the machine answers a single question for you: how far away from zero was the value that you put in?

The basic operation of the machine is simple. Take any number, put it into the machine, and find out how far from zero that number is. The absolute value of 12, |12|, is equal to 12. The absolute value of -10, |-10|, is equal to 10. That’s because -10 is 10 units away from zero.

It starts to get complicated when the GRE asks you to put things into the machine that are more complex than simple numbers. Imagine that somebody else is operating the machine. She puts values in, but she doesn’t tell you what those values are. All you can see is the answer that the machine gives when it receives those values. Read more

GRE Math for People Who Hate Math: What Is a Variable, Really?

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Manhattan Prep GRE Blog - GRE Math for People Who Hate Math: What is a Variable, Really? by Chelsey Cooley

You can attend the first session of any of our online or in-person GRE courses absolutely free. Crazy, right? Check out our upcoming courses here.


Imagine a world where every conversation went like this:

Student: When is our final project due?

Professor: Three days after the first Wednesday after your rough draft is due.

Student: What?

Professor: The rough draft is due 15 days after the date 6 days before May 14.

Solving a GRE math word problem is a little bit like having this kind of conversation. That’s why word problems can be so infuriating. The problem isn’t lying to you. It’s just telling you the truth in a really annoying, backwards way. (Reading Comprehension problems do that too—it’s not just a Quant thing.)

In the conversation above, how would you work out the due date of the final project? Personally, I’d start by getting out my calendar. I’d start at May 14, then count 6 days backwards. Then, I’d count 15 days forwards, put a star on the calendar, and mark it ‘rough draft.’ Then I’d find the first Wednesday after that date, and finally, I’d count three days forward from there. That would give me my answer. Read more

Solving GRE Problems in Multiple Ways to Build Flexibility

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Manhattan Prep GRE Blog - Solving GRE Problems in Multiple Ways to Build Flexibility by Cat Powell

Did you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


Recently, my colleague Tom and I decided that, since we were teaching in adjacent classrooms, it might be fun to combine our classes and co-teach a lesson. Tom and I have very different strengths, both as test-takers and teachers. I love algebra, and I’ll always seek out an algebraic solution to a problem (even when this might not be the most efficient method—my strength is also a weakness). Tom prefers non-algebraic methods, like drawing diagrams or picking numbers. And our strengths inform what we emphasize in class.

So, for our joint lesson, we chose a number of GRE problems that could be solved in more than one way, and then took turns demonstrating each method. First, we each used the method we preferred (algebra for me, picking numbers for Tom), and then we switched and demonstrated the method we were less comfortable with. Here’s one of the GRE problems we used: Read more

GRE Percent Change Questions

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Manhattan Prep GRE Blog - GRE Percent Change Problems by Neil Thornton

Did you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


One of the most common mistakes many students make on the Quant section of the GRE is to misread percent questions, especially ones that ask you to calculate percent change (i.e. increase, decrease, more, less, greater, discount, or profit). You can fix this issue with a bit of practice, but it requires some careful reading on your part. Read more

GRE Prime Factorization and Divisibility Problems

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Manhattan Prep GRE Blog - GRE Prime Factors and Divisibility Problems by Cat Powell

Did you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


Here’s a hard problem that I used to teach in session 1 of our GRE course (my poor students! This was a rough intro to GRE math.)

Manhattan Prep GRE Blog - GRE Prime Factorization and Divisibility Problems by Cat Powell

If you’d like to, give yourself a minute or two to try this (but don’t bang your head against it for too long). If you’re thinking wow, I have no idea what’s going on here—well, it’s a good thing you’re reading this. And even if you do feel comfortable with this problem, it might be worth reading further to see how the techniques used to solve this are more broadly applicable in GRE Quant. Read more

Tackling GRE Word Problems: One Thing at a Time

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Manhattan Prep GRE Blog - Tackling GRE Word Problems: One Thing at a Time by Neil Thornton

Did you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


“The man who moves a mountain begins by carrying away small stones.” -Confucius

Recently, one of my students emailed me the following question. I imagine at some point in your GRE practice you’ve run into the same issue: Read more

GRE Math for People Who Hate Math: Backsolving

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Manhattan Prep GRE Blog - GRE Math for People Who Hate Math: Backsolving by Chelsey Cooley

Did you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


You know what I love about GRE Discrete Quant problems? Specifically, multiple-choice Discrete Quant? The answer choices. Think about it: out of the infinite number of numbers in the universe, the GRE has already narrowed it down to just five possibilities. They’ve done almost all of the work for you. And that makes Discrete Quant a huge opportunity for People Who Hate Math. Read more

GRE Math for People Who Hate Math: Which of the Following is a Factor of x?

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Manhattan Prep GRE Blog - GRE Math for People Who Hate Math:  Which of the Following is a Factor of x? by Chelsey CooleyDid you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


Did you know that you can solve ‘which of the following is a factor’ problems with hardly any math at all? It just takes a little basic arithmetic, logical reasoning, and creative thinking — skills that you already have.

Take a quick look at this problem: Read more

GRE Geometry: Three ways to spot similar triangles

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Manhattan Prep GRE Blog - GRE Geometry: 3 Ways to Spot Similar Triangles by Chelsey CooleyDid you know that you can attend the first session of any of our online or in-person GRE courses absolutely free? We’re not kidding! Check out our upcoming courses here.


Certain diagrams appear in tough GRE Geometry problems over and over again. Here are three of our favorites:

Manhattan Prep GRE Blog - GRE Geometry: 3 Ways to Spot Similar Triangles: Diagram 1

What these three diagrams have in common is that they’re all composed of similar triangles. If you learn to  spot them at a glance, you won’t waste time trying to prove that the triangles are similar.  You’ll simply recognize that fact, and move on to the next step of the problem. Read more