Given:
Two cards are drawn from a standard deck of 52 cards without replacement.
To find:
The probability that both cards selected for black.
Solution:
We know that,
Total number of cards = 52
Total number of red cards = 26
Total number of black cards = 26

Probability of selecting first black card is


Number of remaining total cards = 52-1 = 51
Number of remaining black cards = 26-1 = 25
Probability of selecting second black card is

So, the probability that both cards selected for black is


Therefore, the required probability is
.