statistic
posted by Tian .
A business firm considers the number of years of formal education, X, a prime factor in screening applicants for employment in its plant. Assume from past experience that X ~ N (10.6, 2.5), where 10.6 is the mean and 2.5 is the standard deviation.
(a) If an applicant falls into the lower 20% (lowest quintile) educationally, then the applicant is automatically eliminated from consideration for employment. What cutoff point, in terms of number of years of formal education, is being used?
(b) If an applicant falls into the upper 25% (highest quartile) educationally, then it is felt that the applicant is overeducated for the job, and is also eliminated from consideration. What upper cutoff point, in terms of years of formal education, is being used?

Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions indicated. Use the corresponding Z scores to find the scores with the equation above.