GMAT Equations

Question 1

x^n * x^m =

Answer 1

x^(n+m)

Question 2

(x^n) / (x^m) =

Answer 2

x^(n-m)

Question 3

(x/y)^n =

Answer 3

x^n / y^n

Question 4

x^n * y^n =

Answer 4

(xy)^n

Question 5

(xy)^z =

Answer 5

x^z * y^z

Question 6

x^-n =

Answer 6

1/x^n

Question 7

1^n=

Answer 7

1

Question 8

x^0 =

Answer 8

1

Question 9

0^n =

Answer 9

0 (Note: 0^0 is considered an indeterminate form)

Question 10

Future Value =

Answer 10

Current Value * (1 + growth rate)^Time

Question 11

Distance =

Answer 11

Speed * Time

Question 12

Wage =

Answer 12

Rate * Time

Question 13

(a/b) / (c/d) =

Answer 13

(a/b) * (d/c)

Question 14

Percent change =

Answer 14

(New - Old) / Old

Question 15

New Value =

Answer 15

(1 + Growth Rate) * Old Value

Question 16

Probability of Event E =

Answer 16

P(E) = Number of favorable outcomes / Total number of outcomes

Question 17

P(not E) =

Answer 17

1 - P(E)

Question 18

P(E or F) =

Answer 18

P(E) + P(F) - P(E and F)

Question 19

P(E and F) =

Answer 19

P(E) * P(F) (If E and F are independent events)

Question 20

Sum of Interior Angles of a Polygon =

Answer 20

(n-2) * 180 (where n = number of sides)

Question 21

Central Angle =

Answer 21

2 * Inscribed Angle

Question 22

Square: A =

Answer 22

side^2

Question 23

Rectangle: A =

Answer 23

length * width

Question 24

Parallelogram: A =

Answer 24

base * height

Question 25

Trapezoid: A =

Answer 25

0.5 * (base1 + base2) * height

Question 26

Circle: A =

Answer 26

πr^2

Question 27

Central angle =

Answer 27

2(inscribed angle)

Question 28

Sector of a Circle =

Answer 28

(central angle/360) * πr^2

Question 29

Square: P =

Answer 29

4 * side

Question 30

Rectangle: P =

Answer 30

2 * (length + width)

Question 31

Circle: C =

Answer 31

2πr

Question 32

Triangle: A =

Answer 32

0.5 * base * height

Question 33

Cube: V =

Answer 33

side^3

Question 34

Rectangular solid (Box): V =

Answer 34

length * width * height

Question 35

Cylinder: V =

Answer 35

πr^2h

Question 36

Cone: V =

Answer 36

(1/3)πr^2h

Question 37

Pyramid: V =

Answer 37

(1/3)(base * width * height)

Question 38

Sphere: V =

Answer 38

(4/3)πr^3

Question 39

Simple Interest: Interest =

Answer 39

Principal * rate * time

Question 40

Compound Interest (annually): Interest =

Answer 40

Principal * (1 + rate)^time

Question 41

Compound Interest (compounded n times per year): Interest =

Answer 41

Principal * (1 + rate/n)^(n*time)