Basic probability

Basic  probabilityProbability or chance can be measured on a scale which runs from zero, which represents

impossibility, to one, which represents certainty.A sample space, , is the set of all possible outcomes of an

experiment. An event  is a subset of .

Combinations of eventsGiven events ,and B, further events can be identified as follows.·        

The complement of any event , written  or , means that  does not occur·        

The union of any two events  and B written , means that  or B or both occur.The intersection of any two

events  and B written , means that both  and B occur.....

The probability of the union of a set of mutually exclusive events

is the sum of their separate probabilities....

The probability of the union of a set of mutually exclusive events

is the sum of their separate probabilities...

The probability of a certainty is unity...

The probability of the joint occurrence of two statistically independent

events is the product of their individual or marginal probabilities...The conditional probability of the

occurrence of the event A given that the event B has occurred is the probability of their joint

occurrence divided by the probability of B...