Quick Notes

Quick Notes

Mathematics Chapter 13: Simple Probability
13.2 The Probability Theory Involving Equally Likely Outcomes
 
13.2  The Probability Theory Involving Equally Likely Outcomes
 
Sample space for an experiment:
 
  Definition  
     
 
  • Sample space is a set of all possible outcomes of an experiment.
  • It is represented with the letter \(S\).
  
 
  • A tree diagram can be used to show the flow of the process.
  • It is used to organise and calculate the probability of an event happening.
   
Example
   
   
Event of an experiment:
 
  Definition  
     
 

Event is a set of possible outcomes that fulfill certain conditions for a sample space and is a subset for the sample space.

  
 
Probability of an event:
 
  • The number of possible outcomes is represented by \(n(S)\) .
  • The number of events is represented by \(n(A)\).
  • The probability of an event \(A\) is \(P(A)\).
 

Then, the probability of an event \(A\) is represented by 

\(P(A) = \dfrac{n(A)}{n(S)}.\)