SOLUTION: A box contains five balls numbered 1, 2, 3, 4 and 5. Three balls are randomly
selected without replacement. What is the probability that the median of
the values on the selected
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-> SOLUTION: A box contains five balls numbered 1, 2, 3, 4 and 5. Three balls are randomly
selected without replacement. What is the probability that the median of
the values on the selected
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Question 1192894: A box contains five balls numbered 1, 2, 3, 4 and 5. Three balls are randomly
selected without replacement. What is the probability that the median of
the values on the selected balls is less than 4? Express your answer as a
common fraction.
Can I get hep on solving this? Thank you for your time and help. Answer by greenestamps(13203) (Show Source):
The number of possible combinations of 3 of the 5 balls is "5 choose 3":
For the median of the three selected balls to be NOT less than 4, the median must be ball 4; that means the three balls are 4, 5, and one of the other three. The number of combinations with that requirement is 3 choose 1, which is 3.
So the probability of getting a median that is 4 is 3/10; and of course there is no way to get a median of 5.
So finally the probability of the median of the three selected balls to be less than 4 is 1-3/10 = 7/10.
