In a box, there are 8 red, 7 blue and 5 green balls. One ball is picked up randomly. What is the probability that it is neither blue nor red?

Question: In a box, there are 8 red, 7 blue and 5 green balls. One ball is picked up randomly. What is the probability that it is neither blue nor red?

Solution:
Total number of balls = (8 + 7 + 5) = 20.

Let E = event that the ball drawn is neither blue nor red
= event that the ball drawn is green.
n(E) = 5
P(E) =n(E)/n(S) = 5/20 = 1/4