A bag contains 4 red, 6 blue and 8 green identical marbles. (a) If three marbles are drawn at random, without replacement, calculate the probability that : ...

A bag contains 4 red, 6 blue and 8 green identical marbles.

(a) If three marbles are drawn at random, without replacement, calculate the probability that :

(i) all will be green ; (ii) all will have the same colour.

(b) If each marble is replaced before another is drawn, calculate the probability that all will have the same colour.