Question 1018122: A bag contain 7 yellow 3 red and 5 green marbles.Jack draws two marbles at random without replacement .What is the probability that none of the marbles are red?
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! It is 1-probability that both are-probability that 1 is.
probability both are is (3/15)(2/14)=6/210
probability one is: 2 (3/15)(12(14) OR (3/15)(12/14)+(12/15)(3/14), and they are the same, so I just double it
72/210.
The sum is 78/210, and I subtract that from 1, or 210/210 to get 132/210 or 44/70.
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second way
probability both aren't is (12/15)(11/14)=132/210, 44/70.
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