Answer : let A denote the event that the card drawn is spade and B denote the event that card drawn is king.

In a pack of 52 cards, there are 13 spade cards and 4 king cards

Given : P(A) = 13/52   , P(B) = 4/52

To find : Probability that card drawn is either a queen or heart = P(A or B) The formula used : Probability =

P(A or B) = P(A) + P(B) – P(A and B)

P(A) =     (as favourable number of outcomes = 13 and the total number of outcomes = 52)

P(B) =     (as favourable number of outcomes = 4 and the total number of outcomes = 52)

The probability that card is drawn is both spade and king = P(A and B)= 1 (as there is one card which is both spade and king i.e. king of spades)

P(A or B) =  13/52  +  4/52      1

P(A or B) = 4/13

P(A or B)= 4/13

Probability of a card drawn is either a spade or king = P(A or B) = 4/13