Question 187965
The average salary for graduates entering the actuarial field is $40.000. If the salaries are normally distributed with a standard deviation of $5000, find the probability that 
a.) An individual graduate will have a salary over $45,000.
z(45000) = (45000-40000)/5000 = 1
P(x > 45000) =  P(z > 1) = 0.1587
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b.) A group of nine graduates will have a group average over $45,000.
z(45000) = 5000/(5000/sqrt(9)) = 3
P(x-bar > 45000) = P(z>3) =0.0013
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Cheers,
Stan H.