The probability that the first card selected is a black card and the second card selected (after replacement) is a red card is 1/4
In a standard deck of 52 cards, half are black (26 black cards) and half are red (26 red cards).
P( first card being black) = Probability of black card = 26/52 = 1/2
P(second card being red (after replacement) = Probability of red card = 26/52 = 1/2
The events are independent due to replacement, the probability of both events occurring is the product of their individual probabilities:
Probability of first card being black and second card being red = (1/2) * (1/2) = 1/4