SOLUTION: two bad light bulbs get mixed up with seven good ones.if you take two of the bulbs, what is the probability that both are bad?

Question 1124055: two bad light bulbs get mixed up with seven good ones.if you take two of the bulbs, what is the probability that both are bad?
Answer by Alex.33(110) (Show Source): You can put this solution on YOUR website!
number of cases-
get 2 bad ones: 1 case(since there are only 2 bad bulbs).
get 2 randomly(overall):2c9=36.
probability=1/36 (since they are chosen randomly the possibility for all possibilities should be the same)
And we're done. This is a fundamental approach when it comes to random selection and probabilities: go to the number of cases included, instead of playing with abstract probabilities.
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