Ulysses Mortgage Associates: Credit Scores

The credit score of a 35 year old applying for a mortgage at Ulysses Mortgage Associates is normally distributed with a meanof 600 and a standard deviationof 100.
(a) Find the credit score that defines the upper 5 percent.
(b) Seventy-five percent of the customers will have a credit score higher than what value?
(c) Within what rangewould the middle 80 percent of credit scores lie?

This is a solution calculating the credit scores based on the mean and standard deviation of Ulysses Mortgage Associates.