Exhaustive Events.

Exhaustive Events

The total number of possible outcomes in any trial is known as exhaustive events or exhaustive cases. For example
(i) In tossing of a coin there are two exhaustive cases, viz., head and. tail[ (the possibility of the coin standing on an edge being ignored).
(ii) In throwing of a die, there are six, exhaustive cases since anyone of the 6 faces 1,2, ... ,6 may come uppermost.
(iii) In drawing two cards from a pack of cards the exhaustive number  cases is ⁵²C₂ since 2 cards can be drawn out of 52 cards in ,⁵²C₂ways.
(iv) In throwing of two dice, the exhaustive number of cases is 6² = 36, since any of the 6 numbers 1.to 6 on. the first die. can be associated with any of the six numbers on the  other die.

In general in throwing of n dice the exhaustive number of cases is 6

Favorable Events or Cases. 

The number of cases favorable to an event'in a trial is the number of outcomes which entail the happening of the event For example,
(i) In drawing a card from a pack of cards'the number of cases favorable to drawing of an ace is 4, for drawing a spade is 13 and for drawing a red card is 26.
(ii) In throwing of two dice, the number of cases favorable to getting the sum 5 is : (1,4) (4,1) (2,3) (3,2), i.e., 4.