What is the probability of drawing a king from deck of 52 cards?
Hence From drawing a card from a deck, each outcome has probability 1/52. The probability of an event is the sum of the probabilities of the outcomes in the event, hence the probability of drawing a spade is 13/52 = 1/4, and the probability of drawing a king is 4/52 = 1/13.
What is the number of favorable outcomes?
The number of favorable outcomes is the number of choices (such a rolling a two on a die) and the probability is found by comparing this to the total number of outcomes (six in case of a die.) Arithmetic can be used to calculate outcomes.