SOLUTION: In a sample of 600 students, 150 are seniors. If two students are selected at random from the sample, find the probability both students are seniors.
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Question 474485: In a sample of 600 students, 150 are seniors. If two students are selected at random from the sample, find the probability both students are seniors.
You can put this solution on YOUR website! In a sample of 600 students, 150 are seniors. If two students are selected at random from the sample, find the probability both students are seniors.
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The probability that the 1st is a senior is P(1st) = 150/600
Once the first is selected, there is one fewer student and one fewer senior.
So the probability that the 2nd is a senior is P(2nd) = 149/599
The probability that both are seniors is the product of these:
P(both) = P(1st)P(2nd) = 150/600*149/599 = 1/4*149/599 = 0.0622
