1. Conditional probability Probability of an event E, given that an event F has occurred is called the conditional probability of E given F, and is written as P(E|F).

2. Formula for Conditional Probability P(E|F)=P(EF)/P(F), if P(F)≠0 P(EF) = P(F).P(E|F) OR P(EF) = P(E). P(F|E)

3. Independent Events If the probability of event E does not change even though the event F has occurred, then we say that the events E and F are independent events. If E and F are independent events we have the following properties: 1. P(E) = P(E|F) 2. P(F) = P(F|E) 3. P(EF) = P(E).P(F) 4. P((EF)|G) = P(E|G).P(F|G), given G has occurred