A bag contains 8 red, 3 white and 9 blue balls. If three balls are drawn at random, determine the probability that (i) all the three balls are blue balls 9ii) all the balls are of different colours

given: bag which contains 8 red, 3 white, 9 blue balls

formula:


three balls are drawn at random therefore


total possible outcomes of selecting two persons is 20C3


therefore n(S)=20C3=1140


(i) let E be the event that all the balls are blue


E= {B, B, B}


n(E)= 9C3=84




(ii) let E be the event that all balls are of different colour


E= {B W R}


n(E)= 8C13C19C1=216




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