A card is drawn from a standard deck of 52 playing cards. What is the probability that the card is an ace or a king?

##2/13##

There are 52 cards in a standard deck: 13 ordinal cards (Ace - 10, Jack, Queen, King) and 4 of them - one to each suit (hearts, diamonds, clubs, spades) and so we have ##4xx13=52##.

There are 8 cards that fit the question (4 each of aces and kings).

And so in a random draw, the odds of drawing one of those 8 cards out of the total number of 52 is:

##8/52##

which we can simplify:

##8/52=2/13##