Independent Events
Several events are said to be independent if the happening (or non-happening) of an event is not affected by the supplementary knowledge concerning the occurrence of any number of the remaining events. For example,
In tossing an unbiased coin, the event of getting a head in the first toss is independent of getting a head in the second, third and subsequent tosses. Similarly, if we draw two cards from a pack of cards in succession, then the results of the two draws are independent if the cards are drawn with replacement ( that is, if the first card drawn is placed back in the pack before drawing the second card) and the results of the two draws are not independent if the cards are drawn without replacement.
When a die is thrown twice, the result of the first throw does not affect the result of the second throw.
