A bag contains 5 black, 7 red and 3 white balls. A ball is drawn from the bag at random. Find the probability that the ball drawn is:
(i) red
(ii) black or white
(iii) not black
Sample space, n(S) = 15
(i) n(E) = 7
(ii) n(E) = 10
(iii) n(E) = 5