Probability of event

Question

A box is filled with 9 red cards, 3 yellow cards, and 3 green cards. A card is chosen at random from the box. What is the probability that it is a red or a green card?

Answer 1

P(A) = n(A)/n(s)

• P(A) = Probability of event A occurring
• n(A) = the number of ways event A can occur = 9 red + 3 green = 12
• n(S) = Total possible outcomes = 9 red + 3 yellow + 3 green = 15

 

P(A) = n(A)/n(s)

P(red or green card) = 12/15 = 4/5