Question 1100933: As an incentive to do homework, Professor Rouse randomly draws three students' names, and they are expected to explain a homework problem of the day. On a particular day, 8 students have not done homework and 17 have. Find the following probabilities.
(a) The first two drawn have not done homework and the third has.
(b) All three drawn have not done homework.
(c) All three drawn have done homework.
(d) At least one of the three drawn has done homework.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! As an incentive to do homework, Professor Rouse randomly draws three students' names, and they are expected to explain a homework problem of the day. On a particular day, 8 students have not done homework and 17 have. Find the following probabilities.
(a) The first two drawn have not done homework and the third has.
Ans: [8C2/25C2][17/25] = (28/300)(17/25) = 0.0635
(b) All three drawn have not done homework.
Ans:: 8C3/25C3
(c) All three drawn have done homework.
Ans: 17C3/25C3
(d) At least one of the three drawn has done homework.
Ans:: 1-[8C3/25C3]
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Cheers,
Stan H.
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