Home > probability > What is Probability? What is Probability? probability If S is the sample space of a random experiment, ‘E’ is any event, then probability of E is denoted by P(E) and is defined as P(E) = (Number of Simple Events in E / Total Number of Simple Events in S.) Note that, P(φ) = 0 and P (S) = 1 Share Tweet +1 Share Pin What Others Are READING Leave a Reply Cancel reply Your email address will not be published. Required fields are marked *Name (required) Email (required) Website