SOLUTION: An applicant must score at least 80 points on a particular psychological test to be eligible to join Canadian University services overseas. From several years of experience, it is

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Question 1168116: An applicant must score at least 80 points on a particular psychological test to be eligible to join Canadian University services overseas. From several years of experience, it is known that 60% of the applicants meet the requirement. Let the random variable x be the number of applicants who meet this requirement out of a (randomly selected) group of 25 applicants.
a)find the mean of x
b) Find the standard deviation of x
c) using the Empirical Rule, within what limit would you expect most (say, 95%) of the measurements to be?

Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
mean is np or 25*0.60=15
variance is np(1-p) or 15*0.4=6
sd is sqrt (V)=2.45
empirical rule for 95% is +/- 2 sd or +/- 4.9
(5.2, 24.8)