GRE Math Formulas Cheat Sheet

By Chris on December 14, 2011 in Math Concepts

Before walking into the GRE, it is a good idea to know the following formulas/tidbits. In fact, not knowing the information below can seriously hurt your chances of answering a question correctly.

At the same time, while this is a very useful cheat sheet, do not just memorize formulas without actually applying them to a question. Often students will see a question and will assume that a certain formula is relevant. This is not always the case. So make sure you practice using the formulas so you will know when they pertain to a question.

Interest

Simple Interest: V=P(1+rt/100) , where P is principal, r is rate, and t is time

Compound Interest: $V=P(1+r/{100n})^nt$ , where n is the number of times compounded per year

Work Rates

{1/TotalWork}={1/WorkRate1}+{1/WorkRate2}

Sets

{A+B}-{({A}bigcup{}{}{ B})}

Distance, Rate, and Time

D=rt , Distance=Rate*Time

Circles

$Area=pi{r}^2$

Circumference=2pi{r}

Arc Length={x/360}2{pi}r

$Area of sector={x/360}{pi}r^2$

Squares

Perimeter=4s , where s = side

Area = s^2

Rectangles

Area = l*w , where l = length and w = width

Perimeter = 2l+2w

Trapezoids

{{Base1+Base2}/2}*height

Polygons

Total degrees = 180(n-2) , where n = # of sides

Average degrees per side or degree measure of congruent polygon = 180(n-2)/n

The Distance Formula

$sqrt{({x_2}-{x_1})^2+({y_2}-{y_1})^2}$

Prime numbers and integers

1 is not a prime. 2 is the smallest prime and the only even prime.

An integer is any counting number including negative numbers (e.g. -3, -1, 2, 7…but not 2.5)

Fast Fractions

{1/x}+{1/y}={x+y}/{xy} i.e. {1/2}+{1/5}={2+5}/{2*5}=7/10

Divisibility

3 : sum of digits divisible by 3

4 : the last two digits of number are divisible by 4

5 : the last digit is either a 5 or zero

6 : even number and sum of digits is divisible by 3

8 : if the last three digits are divisible by 8

9: sum of digits is divisible by 9

Combinations and Permutations

nCr={n!}/{r!(n-r)!} n is the total number, r is the number you are choosing

nPr={n!}/{(n-r)!}

Probability

Probability of event = {number of ways that fit the requirement}/{number of total ways}

By the way, students who use Magoosh GRE improve their scores on average by 8 points on the new scale (150 points on the old scale.) Click here to learn more.

About the Author

Chris has been helping students excel on the GRE, GMAT, and SAT for the last 10 years. He is the Lead Content Developer and Tutor for Magoosh. His favorite food is wasabi-flavored almonds.

← GRE Vocabulary Words from Merriam-Webster’s “People’s Favorite Words”

Best GRE Prep Books and Resources 2011 →

8 Responses to GRE Math Formulas Cheat Sheet

Jhinuk February 2, 2012 at 9:52 am #

Good Job…

Reply
Zahid February 14, 2012 at 1:24 am #

Hi Chris,

Is there any intrigation and differentiation match problems in revised GRE exam?

Reply
- Chris February 14, 2012 at 11:45 am #
  
  No calculus – nor for that matter trig., logarithms, etc.
  
  Reply
Zahid February 15, 2012 at 12:21 am #

Thanks for your kind help!

Reply
Glory May 7, 2012 at 4:31 am #

I was searching for GRE maths formula. Chris, Is the list complete and is it that actual GRE maths question will walk around these formulas?

Reply
- Chris May 7, 2012 at 11:14 am #
  
  Hi Glory,
  
  Interesting that you ask . We are coming out with a Math formula e-book in a few weeks! There the formula list will be far more comprehensive than the one above. Stay tuned!
  
  Reply
  - Glory May 8, 2012 at 4:25 am #
    
    Chris,
    Thank you for replying . I would really appreciate if you could post me the compiled eBook at : glorybasumata@hotmail.com
    
    Thank You.
    
    Reply
    - Chris May 8, 2012 at 11:49 am #
      
      Hi Glory,
      
      Actually, we will have the download link up on the blog in a few short weeks (you can just check back in then . Also, if you are a Premium Magoosh user the link will automatically show up on your resource page. (You can always check out the free trial version of our product to see how Magoosh can help).
      
      Reply