7 Tips for GRE Quantitative Comparison Questions

The GRE Quantitative Reasoning section can be tricky for even the best math students. It assesses your ability to think critically about math and use foundational mathematical principles in a variety of scenarios.
The Quantitative Reasoning section is made up of three question types: Quantitative Comparison, Problem Solving, and Data Interpretation. Each section type requires different strategies and approaches. In this article we’ll discuss some tips for Quantitative Comparison questions. 
Quantitative Comparison presents two quantities, and sometimes additional information centered above the quantities—often a graph, an equation, or a geometric shape. Check out this example:
quantitative comparisons
The given information is x > 0. The problem then details the two quantities: A and B. Quantity A in this example is x^2, and Quantity B is x^3. The answers on the Quantitative Comparison question will always be the same, no matter what the quantities or given information. They are as follows:
A. Quantity A is greater.
B. Quantity B is greater.
C. The two quantities are equal.
D. The relationship cannot be determined from the information given.
The trick is to figure out which option is correct based on the information you are given. Quantitative Comparison questions require more than simple problem-solving; it’s important to bring skill and strategy to the section as well. Here are seven tips to help you nail the Quantitative Comparison section of the GRE.

  1. Aim for efficiency, not thoroughness. You’ll have a little over an hour to complete the Quantitative Reasoning section, which will include Quantitative Comparison and other question types. Many test-takers get stuck trying to solve one problem meticulously. But unlike in some of your other math tests, nobody is checking your work; the point is that you find the right answer as quickly as possible. 
  2. Compare the quantities. Because answer choices are identical on all Quantitative Comparison questions, you can focus completely on the given quantities and the given information above, if applicable. Understanding all the information you’re given is one way to improve your speed and efficiency, which is paramount on this section.
  3. Pick numbers. Some Quantitative Comparison problems can be solved backwards. Pick some low-level numbers, like 2 or 3, and plug them into the problem where appropriate. By working backwards you can identify the correct answer quickly.
  4. Start with D. You can make a lot of quick progress on a question by dealing with D, or “The relationship cannot be determined from the information given,” first. We have two methods of approaching this: suspecting D and ruling out D. In suspecting D, we test out the equation. If either value could be bigger, then we select D and move on. If one value is greater or the two values are equal, we can rule out D.
  5. Avoid the calculator. Digital calculators are available on the GRE, and they will be tempting. But pulling up and using the calculator takes up time and often distracts you from efficiently solving the problem.
  6. Do the math. Sometimes, simply solving is the best way to proceed. If you have exhausted all your tricks and other options, try to fully calculate the problem.
  7. Skip it, and come back. This is the oft-overlooked virtue of the GRE: you can skip a question and return later. Timing is of critical importance on the Quantitative Comparison section. Don’t be afraid to mark questions you aren’t sure about on the computer, and return later. Once you’ve answered the other test questions in the section, you can easily return to the Quantitative Comparison questions before submitting your answers.

Need some help studying for the GRE? Check out Kaplan’s resources.