This one is dependent probability, each time you remove a card without replacing it back in the deck you change the total population with respect to the distribution and ratios
In a typical deck of cards there are 26 black cards and 26 red cards.
Your first draw A consists of a full deck with a total population of 52 cards so your first draw is
26 out of 52 or 26/52
26/52 is 1/2
Since you don't put the first card back, you now have a total population of 51 cards to draw from 25 of them are black because you took one out and 26 are red, so the second draw B will be based on
26 out 51
26/51
Now the probability that both will occur is P(A and B) = P(A) *P(B after A)
1/2 *26/51 = 26/102 this reduces to 13/51
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