Quantitative Reasoning
P(E) individual outcomes are equally likely
# of outcomes / total number of possible outcomes
sum of the interior angle of a polygon
(n-2)180 n is number of sides
area of a trapezoid
1/2 (sum of the lengths of the bases) (heights)
working rate problems
1/hours for comp a + 1/hrs for comp b = 1/ both hours
Ratio 30-60-90
1: root 3 : 2
Ratio 45-45-90
1:1:root 2
circumference or a circle
2 pi r
surface area of a right circular cylinder
2(pi*(r^2))+ 2*pi*r*h
Most common prime numbers
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, 101, 103, 107, 109, 113, 127, 131, 137, 139, 149, 151, 157, 163, 167, 173, 179, 181, 191, 193, 197, 199
degrees of a circle
360 degrees
0!
=1
Parallelogram
A quadrilateral with two pairs of parallel sides opposite sides & Angles congruent
Working around the average formula
Average = Total (sum of all results)/number of results
Odd * Even
Even
Odd - Odd
Even
Dividing Fractions
Invert (reciprocal) the second fraction and multiply
Mutually Exclusive P(E and F) P(E or F)
P(E and F) = 0 P(E or F) = P(E) + P(F)
independent variable P(E and F) P(E or F)
P(E and F) = P(E)P(F) P(E or F) = P(E) - P(F) - P(E)P(F)
Probability that E or F occurs
P(E) - P(F) - P(E and F)
Sets/Venn Diagram
Total people = (X-z) + (Y-z) + z (those with x and y) when given two venn diagrams make a table to make the totals add up
volume of a cylinder
V=πr²h
permutation
a selection of a group of objects in which order is important To figure out the number of combinations n!/k!(n-k)! n: number of them picked k: number of options
Right Triangle Side length
a^2 + b^2 = c^2
quadrilateral
both pairs of opposite sides are parallel opposite sides of a parallelogram also have equal length B*H
Standard Deviation
differences between the numbers and the mean, square the differences, find the average of the squared difference
Even - Odd
odd
Odd * Odd
odd
area of a circle
pi r^2
Union of A and B
set of all elements that are in a or in b or in both
Intersection of A and B
the set of all elements that are in both A and B (if they have no elements then they are mutually exclusive)
triangle sides
the sum of the lengths of any two of the sides is greater than the length of the third side
average speed of a car
total miles traveled / total hours
Quadratic Formula
x = -b ± √(b² - 4ac)/2a ax^2 + bx + c = 0 helpful for finding the factors in a equation