Wednesday, 18 July 2012

Selection through identical balls

You randomly withdraw 3 balls out of a lot containing identical red, identical green and identical blue balls. What is the probability that you get 1 red, 1 green and 1 blue ball given the number of
a) Red balls = 3,  Green balls = 3,  Blue balls = 3
b) Red balls = p,  Green balls = q,  Blue balls = r such that p,q,r>3
c) Red balls = infinity,  Green balls = infinity,  Blue balls = infinity