Probability is expressed as
number of favorable outcomes/number of total outcomes
In a standard deck of cards, the total number of cards is 52.
There are 13 spades in a standard deck. Thus,
probability of selecting a spade = 13/52 = 1/4
There are 26 red cards in a standard deck of cards. Since the first card was replaced, the total number of cards remains 52.
probability of selecting a red card = 26/52 = 1/2
There are 4 queens in a standard deck of cards. Since the second card was also replaced, total number of cards is still 52. Thus,
Probability of selecting a queen = 4/52 = 1/13
Thus, the probability that the first card will be a spade, the second card will be a red card, and the third card will be a queen is
1/4 x 1/2 x 1/13
= 1/104