27 terms

# GMAT

###### PLAY
Area of a square
a^2
area of a rectangle
lw
area of a parallelogram
bh
area of a trapezoid
.5(a+c)h, where a and c are the lengths of the parallel sides
pi
3.1415
area of a circle
pi*r^2
Circumference of a circle
2pir
area of a sector of a circle
(x/360) PIr^2, where x is the degrees of the sector
what does a radian equal (in terms of degrees)
What is the area of a triangle
.5bh (where b and h are right angles)
What is pathagorean theorem
A^2 + B^2 = C^2 where c is hypotenuse of triangle
What is the equation for combinations
order DOESN'T matter (without repetition, like lottery)
C = n! / ((n-k)k!)!
where k = number of objects selected from a pile of n objects
n = total number of objects from which k objects can be selected
what is the equation for permutations
order DOES matter
P = n^r (WITH REPETITION, r is how many you choose, n is total number of choices)
P = n! / (n-r)! (withOUT REPETITION)
where r = number of objects selected from a pile of n objects
n = total number of objects from which r objects can be selected
*if you are selecting all of them the formula is just n!
used to find the roots of polynomial equation of the second degree
x = (-b (+-) SQROOT(B^2 - 4AC)) / 2a
What does it mean to say that the probability of an event happening is impossible
P(E) = 0
What does it mean to say that the probability of an event happening is certain
P(E) = 1
What does P(E) mean
P(E) = number of outcomes in E / total number of possible outcomes.
EX. P({1,3,5}) and total set is {1,2,3,4,5,6}, => P({1,3,5}) = 3/6
What is the Probably that E does not occur?
P(not E) = 1 - P(E)
What does it mean to say that two sets are mutually exclusive events
if the event "E and F" is impossible. P(E and F) = 0
What does it mean tot say that sets A and B are Independent?
Two events A and B are said to be Independent if the occurrence of either even does not alter the probability that the other event occurs
P(A and B) = P(A)P(B)
What is a polygon
closed plane figure formed by three or more line segments (sides) each side intersects exactly two other sides at their endpoints.
What are vertices
points of intersections of the sides of a polygon
How do you find the distance between to lines on a graph?
Pythagorean Theorem
if machine X can produce 1,000 bolts in 4 hours and machine Y can produce 1,000 bolts in 5 hours, in how many hours can machines X and Y, working together at these constant rates, produce 1,000 bolts?
solve for (1/4) + (1/5) = (1/h)
If A and B and do a job in 4 hours when working together at their respective constant rates and A can do the job alone in 6 hours, in how many hours can B do the job alone
solve for (1/6) + (1/B) = (1/4)
What is the equation for distance
D = average speed * time
What is the equation for compound interest
Balance = P (1 + (R/N))^(TN)
P=principle
R = percent annual interest rate (decimal)
N = number of times compounded per year
T = number of years