Conditional probability. Independence of events

Conditional probability. Independent and dependent events.

The probability of occurrence of an event A at the condition, that an event B takes place, is called the conditional probability and calculated by the formula:

where À , Â Å , Ð ( Â ) 0.

The events À , Â Å are independent events , if Ð ( À Â ) = Ð ( À ) · Ð ( Â ).

Otherwise, the events À and  are called dependent events .