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Classical Probability

In the classical definition of probability, each of the outcomes in the experiment has the same likelihood of happening as any of the others. This implies that the outcomes in the sample space S are all equiprobable.

Examples

The roll of a die, the spin of a Roulette Wheel, and picking coloured candies out of a deep opaque jar are just a few of the examples involving the classical definition of probability.

Classical Probability of an Event

The nature of the outcomes in an experiment, in this case each is equally likely to occur as any other, does not change the way the probability of an event E is calculated.

Remembering that an event E is just a subset of the experiment's sample space S, the definition of P(E) is still:

              # of E-outcomes          # of elements in E
P(E) =  _________________  =  _________________   .
               total # outcomes          # of elements in S

 

Last Updated by SAS October 07, 2026, 16:00:54