Question 765580
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(2)}}}
B.) what is the probability of finding in our sample at least 6 but less than 9 such students?
P(6 &#8804; X < 9) = {{{sum((matrix(2,1,10,x))(0.2^x)(0.8^(10-x)),x=6,8)}}} = {{{highlight(0.006365)}}}
C) what is the probability of finding exactly 3 such students( show me the set up formula)
P(X = 3) = {{{(matrix(2,1,10,3))(0.2^3)(0.8^7)}}} = {{{highlight(0.2013)}}}