SOLUTION: Hello! I'm having difficulty with this question! A bag containing 5 white, 6 red and 7 blue balls. If 3 balls are selected at random what is the probability that they are all diffe

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Question 53252: Hello! I'm having difficulty with this question! A bag containing 5 white, 6 red and 7 blue balls. If 3 balls are selected at random what is the probability that they are all different colours?
Well the first can be any so that doesn't matter. But then the Q branches out too much and I dont know the simple way to work it out. THanks!
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
A bag containing 5 white, 6 red and 7 blue balls. If 3 balls are selected at random what is the probability that they are all different colours?
# of ways to select a group of three that has one white, one red, and one blue
is 5*6*7 or 210
# of groups of three balls of any color combination is 18C3=(18*17*16)/(1*2*3)
=816
Prob(3 of different colors)= 210/816= 0.257
Cheers,
Stan H.