1. Probability

2. NOTE 1: Definitions
Probability is a measure of how likely it is that an event will happen. It can be expressed as a fraction or a decimal point and is on a continuum between 0 and 1.
¼ ½ ¾
Impossible unlikely may or may likely will definitely not occur occur

3. An experiment is a process with a result that depends on chance.
Example: Picking a card from a pack of 52
A trial is one perfomance of an experiment.
Example: Picking a card once
An outcome is the result of a trial.
Example: Getting the 9 of Hearts
The sample space (S) is the set of all possible outcomes of an experiment.
Example: S = {Ace H, King H, … A Spades}
An event (E) is a subset of the sample space.
Example: E = Getting a Club

4. Experimental Probability
The results of experiments allow us to determine relative probabilities from patterns in the past. P(event) = the number of times the event occurs total number of trials

5. Examples:
Find the probability that a student in the IB class has blue eyes. P(Blue eyes) =
The probability an event will not occur = 1 – P (event)
Find the probability that a student in the IB class does
NOT have blue eyes.
P(Not Blue eyes) = 1 – P(Blue eyes)

6. Standard Level:
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Exercise 19A
Studies:
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Exercise 16A.1 – A.2