Short answer P(at least 1 king) = 0.341158CommentThe easy way to do this is to figure out what the Combinatorics are for no kings. Subtract that result from 1.
Total number of ways of drawing 5 cards - any order.
P(any 5 cards) = 52 C 5
P(any 5 cards) =

P(any 5 cards) = 26 * 51 * 5 * 8 * 49 = 2598960 Note: I did this by canceling 5!.
P(no kings) = 48 C 5
The probability of getting no kings = (48 C 5) / 52 C 5 = 0.65884
The probability of getting at least 1 king = 1 - 0.65884 = 0.34115