Update 6/8/12: Even better than a cheat sheet– download our free GRE Math Formula eBook!
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.
Simple Interest: , where P is principal, r is rate, and t is time
Compound Interest: , where n is the number of times compounded per year
, where T is the time to completion of a task when two workers are combining effort.
Distance, Rate, and Time
, where s = side
, where l = length and w = width
, where n = # of sides
The Distance Formula
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)
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
n is the total number, r is the number you are choosing