Gre Math

Front 1

sq. root of 2

Back 1

1.4

Front 2

sq. root of 3

Back 2

1.7

Front 3

sq. root of 5

Back 3

2.2

Front 4

14^2

Back 4

196

Front 5

13^2

Back 5

169

Front 6

15^2

Back 6

225

Front 7

16^2

Back 7

256

Front 8

20^2

Back 8

400

Front 9

25^2

Back 9

625

Front 10

factor -

x^2 - y^2

Back 10

(x+y) (x-y)

Front 11

x^2 - 4

Back 11

(x+2) (x-2)

Front 12

9 - y^2

Back 12

(3+y) (3-y)

Front 13

Supplementary Angle

Back 13

straight angle, 180 degrees

Front 14

Obtuse angle

Back 14

over 90 degrees but less than 180 degrees

Front 15

Complementary angles

Back 15

Angles that sum up to 90 degrees

Front 16

Reflex Angle

Back 16

Angle that-s greater than 180 degrees but less than 360 degrees

Front 17

Vertical Angle

Back 17

opposite angles and have equal measure

Front 18

Corresponding angle

Back 18

angles that have the same position formed by two parallel lines and a transversal line (that cuts through two parallel lines)

Front 19

Similar figures

Back 19

figures that have congruent angles and proportional sides (size might differ, but proportions stay the same)

Front 20

Area of similar figures

Back 20

Ratio of the area of two similar figures is equal to the ratio of their sides

Front 21

Area of Triangle =

Back 21

1/2 base * height

(height might be outside the triangle)

Front 22

Pythagorean Theorem

Back 22

a^2 + b^2 = c^2

ONLY WORKS ON RIGHT TRIANGLES

Front 23

Ratio 3:4:5

Back 23

In right triangle, ratio of sides

Front 24

Ratio 5:12:13

Back 24

In right triangle, ratio of sides

Front 25

Ratio s:s: sq. root of s remainder 2

Back 25

in Isoscoles right triangle, ratio of sides

Front 26

Ratio of 30:60:90 degree triangle

Back 26

s: s *sq. root of 3 : 2s

Front 27

Area of rhombus

Back 27

A = 1/2 d1 *d2

where d is diagonal

Front 28

Rhombus

Back 28

4 equal sides, four angles not necessarily right angles

Front 29

Area of trapezoid

Back 29

A = 1/2 (b1 + b2) * height

where b is base 1 and base 2.

and height is possibly measured outside the figure (not length)

Front 30

Area of a parallelogram

Back 30

A = b * height

where b is base

Front 31

Area of a circle

Back 31

pi * radius^2

Front 32

Total Interior Angle Measure Formula (TIA)

Back 32

measure of all interior angles of figure.

(n-8)180

where n is number of sides

Front 33

TIA for triangle

Back 33

(3-2)180 = 180

Front 34

TIA for quadrilateral

Back 34

(4-2) *180 = 360

Front 35

TIA for pentagon

Back 35

(5-2) *180 = 540

Front 36

TIA for hexagon

Back 36

(6-2) *180 = 720

Front 37

TIA for heptagon

Back 37

(7-2) *180 = 900

Front 38

TIA for octagon

Back 38

(8-2) *180 = 1,080

Front 39

TIA for nonagon

Back 39

(9-2) *180 = 1,260

Front 40

TIA for decagon

Back 40

(10-2) *180 = 1,440

Front 41

Avg. measure of ONE interior angle formula

Back 41

(n-2)*180 / n

Front 42

Volume of cylinder

Back 42

V = pi *r^2 x height

Front 43

Total surface Area formula (TSA)

Back 43

TSA = 6 x s^2

Front 44

TSA of rectangle

Back 44

TSA = 2(lw) + 2(wh) + 2(hl)

Front 45

TSA of cylinder

Back 45

TSA = circumference x height + 2(pi*r^2)

Front 46

inscribed angle

Back 46

angle that has both endpoints and its vertex on the circumference of the circle. The degree measure of an inscribed angle is half the degree measure of its intercepted arc

Front 47

Length of an arc, formula

Back 47

1. Find circumference of circle

2. Put degree measure of arc over 360 and reduce the fraction

3. Multiply the circumference by the fraction

Front 48

Area of a sector

Back 48

1. Find area of entire circle

2. Put degree measure of sector of 360 degrees and reduce the fraction

3. Mult. area by the fraction

Front 49

FOIL rule

Back 49

when multiplying in algebra,
First Outer, Inner Last

ex. (a + b) (a -b)

Front 50

Consecutive Probabilities

Back 50

In order to find out probability of consecutive events (i.e. tossing coin and landing heads twice in a row):

1. Find probability separately for each

2. then multiply the two

Front 51

DIRT formula

(Distance, Rate, Time)

Back 51

D = Rate x Time

Front 52

Avg. of evenly space terms

Back 52

(first + last) / 2

Front 53

Finding missing term in Avg. problem

Back 53

Avg. = Sum / Number of terms

solve with algebra

ex. 90 = (535 + x) / 7

Front 54

Percent increase / decrease

Back 54

= (Number increase or decrease) / original whole

1. Find amount by which the thing has inc. or dec.

2. Find the original whole (not total whole)

Front 55

Zero = prime or composite?

Back 55

not prime, not composite

Front 56

One = prime or composite?

Back 56

not prime, not composite

Front 57

Two = prime or composite?

Back 57

prime

Front 58

Interest formula

Back 58

PRT = I,

where
P = principal amount
R = Rate of interest
T = Time
I = Interest

Front 59

Work formula

Back 59

work = Time put in / Capacity

Front 60

Order of Operations

Back 60

1. parentheses
2. power
3. Mult. or divide
4. Add or subtract

Front 61

1 lb = ?? oz

Back 61

16 oz

Front 62

1 Ton = ?? lbs

Back 62

2,000 lbs

Front 63

1 pint = ?? cups

Back 63

2 cups

Front 64

1 qt = ?? pints

Back 64

2 pints

Front 65

1 gallon = ?? qts

Back 65

4 qts

Front 66

1 mile = ?? feet

Back 66

5,280 feet

Front 67

1 mile = ?? yds

Back 67

1,760 yds

Front 68

"Figure not drawn to scale"

Back 68

often answer is D, not enough information

Front 69

Sacred Six numbers

Back 69

Use to plug in when there are variables in deciding which answer is greater

In this order:

1, 2, 0, -1, -2, 0.5

Front 70

What to insert with variety of variables

Back 70

consecutive numbers, then non-consecutive numbers for a, b, c