SOLUTION: Please help me with this problem: 20% of the students on campus are from California A random sample of 10 students is selected. A.)what is the expected # of California stude

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Question 765580: Please help me with this problem:
20% of the students on campus are from California A random sample of 10 students is selected.
A.)what is the expected # of California students in the sample?
B.) what is the probability of finding in our sample at least 6 but less than 9 such students?
C) what is the probability of finding exactly 3 such students( show me the set up formula)
Answer by reviewermath(1029) About Me  (Show Source):
You can put this solution on YOUR website!
20% of the students on campus are from California. A random sample of 10 students is selected.
A.)what is the expected # of California students in the sample?
Expected Value = np = 10(0.2) = highlight%282%29
B.) what is the probability of finding in our sample at least 6 but less than 9 such students?
P(6 ≤ X < 9) = sum%28%28matrix%282%2C1%2C10%2Cx%29%29%280.2%5Ex%29%280.8%5E%2810-x%29%29%2Cx=6%2C8%29 = highlight%280.006365%29
C) what is the probability of finding exactly 3 such students( show me the set up formula)
P(X = 3) = %28matrix%282%2C1%2C10%2C3%29%29%280.2%5E3%29%280.8%5E7%29 = highlight%280.2013%29