Question

A card is drawn at random from a pack of 52 cards. Find the probability that the card drawn is spade or an ace

Answer 1

Let S denote the sample space.
Then, n(S) = 52

 Let E₆ = event of drawing a spade or an ace
      There are 13 spade cards including one ace. Also, there are 3 more ace cards.
      Therefore, out of these 16 cards, one can draw either a spade or an ace in ¹⁶C₁ ways.
       i.e. n (E₆) = 16
     ∴ \[P\left( E_6 \right) = \frac{n\left( E_6 \right)}{n\left( S \right)} = \frac{16}{52} = \frac{4}{13}\]