A box contains 5 red marbles, 8 white marbles and 4 green marbles. One marble is taken out of the box at random. What is the probability that the marble taken out will be (i) red ? (ii) white? (iii) not green?

Total number of marbles = 5 + 8 + 4 = 17
(i) Number of red marbles = 5
Probability of getting a red marble = (Number of favorable outcomes)/Number of total possible outcomes) = 5/17
(ii) Number of white marbles = 8
Probability of getting a white marble = (Number of favorable outcomes)/Number of total possible outcomes) = 8/17
(iii) Number of green marbles = 4
Probability of getting a green marble = (Number of favorable outcomes)/Number of total possible outcomes) = 4/17
Probability of not getting a green marble = 1 – 4/17 = 13/17