The probability of drawing a spade is 13/52 = 1/4
Because every hand has 13 cards and there is 52 cards in a deck
The probability of drawing a 7 is 4/52 or 1/13
Because there are seven 7 cards in a deck and 52 cards.
I haven’t done this in a while, but I believe that the “of” in the equation means multiply so you do 3/4 x 1/3 to get 3/12 (simplified to 1/4)!!