MATH: PROBABILITY 1ST QTR

Probability of an event

Measure of the likelihood that an event will happen; P(E) = number of fav. outcomes/total number of possible outcomes

Permutation

Arrangement where in the order matters

Combination

Arrangement where in the order DOES NOT matter

Probability of a complement

P(E’) = 1 - P(E)
P(E) + P(E’) = 1

Estimating the number of outcomes

If we know the probability of an event we can estimate the number of times we expect that event to take place; Expected no. of successful outcomes = probability of success x total number of outcomes

100%

Certain

75%

Likely

50%

As likely as not

25%

Unlikely

0%

Impossible

Mutually Exclusive Events

2+ events that CANNOT happen at the same time

Non-Mutually Exclusive Events

2+ events that can happen at the same time

Dependent event

Any event in which one event is dependent to the occurrence of the other events

Independent Events

Any event in which one even is not dependent on the other

Random experiment

Process that generates a set of data where each outcome is by chance

Sample space

All possible outcomes (S)

Sample point

Element of the sample space

Event

Well defined subset

Simple event

The events where one experiment happens at a time and it will be having a single outcome

Probability of Union of Events MUTUALLY EXCLUSIVE

P(A∪B) = P(A) + P(B)

Probability of Union of Events NON-MUTUALLY EXCLUSIVE

P(A∪B) = P(A) + P(B) - P(A∩B)

Amount of cards in a standard deck

52

Amount of aces in a standard deck

4

Amount of face cards in a standard deck

12

Amount of number cards in a standard deck

36

Types of Suits

Spades, Clubs, Hearts, Diamonds

Amount of black and red suits

26 each

Probability of Intersection of Events

P(A∩B) = P(A) × P(B)