SOLUTION: As part of a monthly inspection at a hospital, the inspection team randomly selects reports from eight of the 84 nurses who are on duty. (a) What is the probability that none of th

Algebra ->  Probability-and-statistics -> SOLUTION: As part of a monthly inspection at a hospital, the inspection team randomly selects reports from eight of the 84 nurses who are on duty. (a) What is the probability that none of th      Log On


   

Question 597204: As part of a monthly inspection at a hospital, the inspection team randomly selects reports from eight of the 84 nurses who are on duty. (a) What is the probability that none of the reports selected will be from the ten most experienced nurses on duty? [Answer is: 0.364] (b) What is the probability that all of the reports selected will be from the 20 least experienced nurses on duty? [Answer is: 0.0000029]
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Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
there are 84C8 ways of getting 8 reports from 84 people

a) no reports from 10 of the people means 8 reports from 74 people ___ 74C8

so probability of none from the 10 is ___ 74C8 / 84C8


b) is similar ___ 8 reports from 20 is ___ 20C8

so probability of all 8 from the 20 is ___ 20C8 / 84C8