please help me solve this problem

Question

please explain to me how to solve this problem:

 

Two cards are selected in sequence from a standard deck of 52 playing
cards. Find the probability that the second card is a queen, given that the
first card is a king. (Assume that the king is not replaced.)

Answer 1

So, we assume that the King is selected and 51 cards remain.  probability of drawing a queen now is 4/51.