The Probability That Event a Will Occur Is $$\mathrm { P } ( \mathrm { A } ) = \frac { \text { Number of successful outcomes } } { \text { Total number of all possible outcomes } }$$

The probability that event A will occur is $$\mathrm { P } ( \mathrm { A } ) = \frac { \text { Number of successful outcomes } } { \text { Total number of all possible outcomes } }$$