6.3.1
Probability
Probability
Probability
The probability of an event is the likelihood of it happening. Probabilities are between 0 and 1 and the higher the probability, the more likely the event is to occur. Probabilities can be given as decimals, fractions or percentages.


Notation
Notation
- For a fair dice, P(6) means the probability of rolling a 6.
- For a bag of coloured balls, P(red) means the probability of a red ball being pulled out.


Relative frequency
Relative frequency
- The relative frequency of an outcome during a probability experiment is an estimate of the probability of that outcome.
- The more trials performed during the experiment, the more accurate the estimate.
Sum of Probabilities
Sum of Probabilities
If all the possible outcomes of an event are listed then the sum of the probabilities of those events will be 1.


Probabilities add up to 1
Probabilities add up to 1
- For any event:
- P(event happens) + P(event doesn’t happen) = 1.
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Rules
Rules
- The probabilities of a set of outcomes add up to 1 if:
- All possible outcomes are included
- Only one outcome can happen at a time.
1Numbers
1.1Integers
1.3Decimals
1.4Powers & Roots
1.5Set Language & Notation
1.6Percentages
1.7Ratio & Proportion
2Equations, Formulae & Identities
2.1Algebraic Manipulation
2.2Expressions & Formulae
2.3Linear Equations
2.4Quadratic Equations
2.5Proportion
3Sequences, Functions & Graphs
3.1Sequences
3.3Graphs
3.4Common Graphs
4Geometry
4.1Angles, Lines & Triangles
4.2Polygons
4.5Circle Properties
4.6Trigonometry & Pythagoras’ theorem
4.7Mensuration of 2D Shapes
4.83D Shapes & Volume
5Vectors & Transformation Geometry
6Statistics & Probability
6.1Statistical Measures
6.2Graphical Representation of Data
Jump to other topics
1Numbers
1.1Integers
1.3Decimals
1.4Powers & Roots
1.5Set Language & Notation
1.6Percentages
1.7Ratio & Proportion
2Equations, Formulae & Identities
2.1Algebraic Manipulation
2.2Expressions & Formulae
2.3Linear Equations
2.4Quadratic Equations
2.5Proportion
3Sequences, Functions & Graphs
3.1Sequences
3.3Graphs
3.4Common Graphs
4Geometry
4.1Angles, Lines & Triangles
4.2Polygons
4.5Circle Properties
4.6Trigonometry & Pythagoras’ theorem
4.7Mensuration of 2D Shapes
4.83D Shapes & Volume
5Vectors & Transformation Geometry
6Statistics & Probability
6.1Statistical Measures
6.2Graphical Representation of Data
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