They can be black or red.
red or black
Red Eyes Black Chick Inferno Fire Blast Red Eyes Darkness Dragon Metalmorph Red Eyes Black Metal Dragon Monster Reborn Decoy Dragon
26/52 times
In a standard deck of cards, all the spades are black.
A penguin with a rash
America
4 in a deck of 52, 2 red, 2 black
The probability is 1. It must be "a red or black card".
There are 2 black 2's and 2 red 3's in a standard deck of 52 cards.
There are two red queens in a standard deck of playing cards: the queen of hearts and the queen of diamonds.
Assuming a full, regular deck, no jokers? There are 52 cards in such a deck, 26 red and 26 black, making the odds of drawing a red card exactly 1 in 2.