You are dealt one card from a 52-card deck. Find the probability that you are dealt a king or a black card.
There are 4 kings in a deck of 52 cards, and there are 26 black cards (13 spades and 13 clubs).
To find the probability of being dealt a king or a black card, we can add the probabilities of being dealt a king and a black card, and then subtract the probability of being dealt both a king and a black card (since that would be counted twice).
The probability of being dealt a king is 4/52 = 1/13.
The probability of being dealt a black card is 26/52 = 1/2.
The probability of being dealt both a king and a black card is 2/52 = 1/26 (since two of the kings are black).
So, the probability of being dealt a king or a black card is:
(1/13) + (1/2) - (1/26) = 2/13 + 13/26 - 1/26 = 3/13
Therefore, the probability of being dealt a king or a black card is 3/13.