2, 3, 5, 7, 11, 13, 17, 19

23, 29, 31, 37, 41, 43, 47

53, 59, 61, 67, 71, 73, 79, 83, 89, 97

Only positive numbers can be prime

even ± even = even

even ± odd = odd

odd ± odd = even

even * even = even

even * odd = even

odd * odd = odd

Zero is even.

positive * positive = positive

positive * negative = negative

negative * negative = positive

positive / positive = positive

positive / negative = negative

negative / negative = positive

Zero is neither positive nor negative, however when GMAT refers to a "non-negative" number that number might be zero.

2: The last digit is even.

3: The sum of the digits is divisible by 3.

4: The last two digits form a number divisible by 4.

5: The last digit is 0 or 5.

6: The number is divisible by both 2 and 3.

9: The sum of the digits is divisible by 9.

10: The last digit is 0.

12: The number is divisible by both 3 and 4.

irrational number: cannot be expressed as a fraction

numerator: The number on top of a fraction.

denominator: The number on the bottom of a fraction.

To add/subtract fractions with the same denominator: Add/subtract the numerator and place over the common denominator.

To add/sub fractions with different denominators: Find the least common denominator and convert the fractions.

To multiply fractions: Multiply the numerators and denominators.

To divide fractions: Invert the divisor fraction (find its reciprocal) then multiply.

$x^0 = 1$

$x^1 = x$

$0^n = 0$

$0^{-n} = undefined$

$1^x = 1$

$x^{-n} = 1/x^n$

$x^n * y^n = (xy)^n$

$(xy)^n = x^n * y^n$

$x^n/y^n = (x/y)^n$

$(x/y)^n = x^n/y^n$

$x^n/y^n = (x/y)^n$

$(x^m)^n = x^{mn}$

$x^n * x^m = x^{n+m}$

$x^{n+m} = x^n * x^m$

$x^n/x^m = x^{n-m}$

$x^{n-m} = x^n/x^m$

$x^{1/n} = √^nx$

$x^{m/n} = √^nx^m$

$x^2 = 25$; solve for x; $x = ±5$

$x^3 = 125$; solve for x; $x = 5$

$x^3 = -125$; solve for x; $x = -5$

$√x * √y = √{xy}$

$√{xy} = √x * √y$

$√x / √y = √{x/y}$

$√{x/y} = √x / √y$

$a√r + b√r = (a+b)√r$

$(a+b)√r = a√r + b√r$

$a√r - b√r = (a-b)√r$

$(a-b)√r = a√r - b√r$

$(√x)^n = √x^n$

$√x^n = (√x)^n$

$x^{1/n} = √^nx$

$√^nx = x^{1/n}$

$x^{n/m} = √^mx^n$

$√^mx^n = x^{n/m}$

$√a + √b ≠ √{a+b}$

$√4 = 2$

$√9 = 3$

$√16 = 4$

$√25 = 5$

$√36 = 6$

$√49 = 7$

$√64 = 8$

$√81 = 9$

$√100 = 10$

$√121 = 11$

$√144 = 12$

$√164 = 13$

$√196 = 14$

$√225 = 15$

$√256 = 16$

$√289 = 17$

$√324 = 18$

$√361 = 19$

$√400 = 20$

$√625 = 25$

$√900 = 30$

$√^3 8 = 2$

$√^3 27 = 3$

$√^3 64 = 4$

$√^3 125 = 5$

$√^3 216 = 6$

$√^3 344 = 7$

$√^3 512 = 8$

$√^3 729 = 9$

$√^3 1000 = 10$

$√^3 8000 = 20$

$2^2 = 4$

$3^2 = 9$

$4^2 = 16$

$5^2 = 25$

$6^2 = 36$

$7^2 = 49$

$8^2 = 64$

$9^2 = 81$

$10^2 = 100$

$11^2 = 121$

$12^2 = 144$

$13^2 = 164$

$14^2 = 196$

$15^2 = 225$

$16^2 = 256$

$17^2 = 289$

$18^2 = 324$

$19^2 = 361$

$20^2 = 400$

$25^2 = 625$

$30^2 = 900$

$2^3 = 8$

$3^3 = 27$

$4^3 = 64$

$5^3 = 125$

$6^3 = 216$

$7^3 = 344$

$8^3 = 512$

$9^3 = 729$

$10^3 = 1000$

$20^3 = 8000$

compound interest = principal * (1 + (interest/C))^{time*C} where C is the number of times compounded annually

Pythagorean Triplets:

3,4,5

5,12,13

8,15,17

Order of Operations:

PEDMAS - Parenthesis, Exponents, Multiplication and Division, Addition and Subtraction

$√2≈1.41$

$√3≈1.73$

$√5≈2.24$

$√6≈2.45$

$√7≈2.65$

$√8≈2.83$

$√10≈3.16$

Overview of the Graduate Management Admissions Test

GMAT Exam Structure and Format

Ace the GMAT Analytical Writing Assessment

GMAT Math Review: Factors and Prime Factorization