A card is drawn at random from a pack of well shuffled deck of playing cards find the probability that the card is (a) a king or a jack (b)a card of spade or an ace (c)red card(d)black face card

Total number of possible outcomes = 52
(a) Number of king = 4
Number of jack = 4

Number of king or jack = 4 + 4 = 8

Probability(king or jack) = $\frac{8}{52}=\frac{2}{13}$

(b) Number of spades = 13
Number of aces = 4
Number of ace of spade = 1

Number of spades or aces = 13 + 4  - 1 =16

Probability(spades or aces) = $\frac{16}{52}=\frac{4}{13}$

(c) Number of red cards = 26

Probability(red card) = $\frac{26}{52}=\frac{1}{2}$
(d) Number of black face cards = 6

Probability(black face cards) = $\frac{6}{52}=\frac{3}{26}$