Answer:
The probability is 0.2, or 20%.
Step-by-step explanation:
A probability is the ratio of the number of relevant outcomes and the number of all possible outcomes. If we know that the marble drawn is not red, the number of possible outcomes N is
N = (number of blue marbles) + (number of green marbles) = 25
and the number of relevant outcomes (marble being green) is n:
n = (number of green marbles) = 5
So, the probability is
P = n / N = 5 / 25 = 1 / 5 or 0.2, or 20%