Question

A box is filled with 7 brown cards, 8 blue cards, and 3 red cards. A card is chosen at random from the box. What is the probability that it is a brown or a red card?

Answer 1

$|\Omega|=7+8+3=18\\ |A|=7+3=10\\\\ P(A)=\dfrac{10}{18}=\dfrac{5}{9}\approx56\%$