Time management | Strategies | Quantitative reasoning

This chapter will discuss perhaps the most ignored aspect of GRE prep: time management. Though it is a more general topic that is somewhat difficult to define, plenty of specific skills fit within the umbrella of time management.

Remember, any time saved during the exam could be spent answering problems elsewhere, and conversely, any time wasted is time that cannot be used on other questions. You should always balance the benefit of taking more time on your current problem versus the cost of taking time away from other problems you have not yet seen.

In other words, you should always consider that there may be other very simple problems at the end of the set that you could easily get right if only you had the time to read them. This not only means that you should not waste too much time on the extremely difficult questions but also not linger on the easy problems because they make you feel comfortable.

Below are several time management strategies that you should develop. Ask yourself if you are adept at each of these skills, and try practicing them as you work through timed practice sets.

Skills of Time Management

Develop an Internal Clock

Developing an internal clock lets you intuitively know when you spend too much time on a problem. This can be achieved by doing many timed practice sets or exams. The average question should be solved in about 1 minute and 45 seconds for the quant section and 1 minute and 30 seconds for verbal, so you should know internally when you are beginning to reach well beyond this average. When this occurs, you should decide whether to guess and move on or push a little further to get to the answer. This should only be done if you have made progress and believe you are close to reaching the answer.

Recognize the Strategy Quickly

Instead of just jumping into each problem, it’s important to take a step back to ask yourself which strategy can be implemented to approach a problem quickly. Look through the following easy difficulty quant questions and practice quickly determining which of these five strategies should be used for each question:

Plug and Play
Using the Answers
Simplify and Compare
Min and Max Extremes
Detect the Misleading Question (Choose D)

1.
Movie A is 30 minutes shorter than Movie B. The total runtime between the two movies is 280 minutes. How long is Movie A?
a. 30
b. 50
c. 100
d. 125
e. 150

2.
QA: The height of a quadrilateral with an area of $88$
QB: The base of a quadrilateral with an area of $88$

3.
$x$ is a prime number between $42$ and $50$
QA: $x$
QB: $43$

4.
$x > - 1$
QA: $x^{2} - x^{3}$
QB: $x^{3} - x^{2}$

5.
$x > 3$
y $> 3$
QA: $(x^{3} - y) /5$
QB: $(3 x^{2} - y) /5$

(spoiler)

Answer:

Using the Answer
Detect the Misleading Question (Choose D)
Min and Max Extremes
Plug and Play
Simplify and Compare

Guess When You Are Stuck

Do not be afraid to guess when you feel you are not making any progress and you are starting to reach 3 minutes on a single question. You can always flag the question and go back later. It is, however, important to guess because you do not know if you will have sufficient time in the end to review the question. For quant comparison questions, the best guess is answer choice D. This is not because D is the most likely answer but because it is the most likely choice, considering that you have not come up with a solution. Your lack of progress on the question may be the reason the relationship cannot be determined!

Use the Calculator When Necessary

Some study materials instruct the students to use the calculator as few times as possible. Though it is certainly beneficial to simplify problems before making final calculations instead of directly writing everything seen into the calculator, that does not mean that one should reject the calculator outright. In fact, using the calculator in appropriate circumstances can help a test taker save time because they are not performing calculating routine operations by hand, and they are not making as many mistakes that would require them to restart the problem.

Memorize Shortcuts

The last and most important skill for time management is to memorize all of the shortcuts. Many GRE questions can be solved in two ways. Oftentimes, there will be one way that is much longer than the other. The test writers are essentially testing to see if you have knowledge of the quicker way.

Here is a list of tools that allow you to solve many GRE questions much quicker. This is not a list of all the equations you will need to know for the exam, rather, it is a list of shortcuts that would PREVENT you from using the equations.

Diagonals

Diagonal of a square:

Diagonal of a square

Diagonal of a cube:

Diagonal of a cube

Ratio of the sides of right triangles

Ratio of 30-60-90 triangle

Ratio of 45-45-90 triangle

Pythagorean triples

$3$ : $4$ : $5$

$5$ : $12$ : $13$

$7$ : $24$ : $25$

Properties of equidistant lists

The median and mean of any equidistant list are identical
The sum of an equidistant list is the product of the mean (or median) and the total number of elements in the list
The average of any equidistant list is the average of the two extremes

Percent change

10% more is 110% or multiplying by 1.1

10% less is 90% or multiplying by .9

The average change in a chart is just the change from start to end divided by the total time from start to end

Common factoring patterns

$x^{2} - y^{2} = (x + y) (x - y)$

$x^{2} + 2 x y + y^{2} = (x + y) (x + y)$

$x^{2} - 2 x y + x^{2} = (x - y) (x - y)$