Discrete Mathematics
# Conditional Probability

A survey on the preference for great composers in the 20$^\text{th}$ century was conducted to 100 music critics. A part of the result is shown in the table below. What is the probability that a randomly chosen critic likes Stravinsky?

$\begin{array}{lcc} & \text{like Schoenberg} & \text{hate Schoenberg} \\ \text{like Stravinsky} & 40 & 25 \\ \text{hate Stravinsky} & 20 & 15 \end{array}$

A card is drawn randomly from a standard deck of cards. What is the probability that the card drawn is a 2 or a Spade?

**Details and Assumptions:**

A standard deck of cards consists of 52 cards, formed by 13 ranks (Ace, 2, 3, 4, 5, 6, 7, 8, 9, 10, Jack, Queen and King) of 4 suits (clubs, diamonds, hearts and spades).