A single card is drawn at random from a wellshuffled deck Co

A single card is drawn at random from a well-shuffled deck. Consider the following events:

A = { the card drawn is a heart }

B = { the card drawn is a club }

How many outcomes does A (union) B have?

Solution

#(A union B) = #(A) + #(B) - #(A intersection B)

Here, #(A) = 13

#(B) = 13

#(A intersection B) = 0 because a card cannot be heart and club

Thus, #(A union B) = # of ways a card drawn is be either heart or club is = 13 + 13 - 0 = 26