For borrowers with good credit scores, the mean debt for revolving and installment accounts is $15,000. Assume the standard deviation is $3000 and that debt amounts are normally distributed.
a) What is the probability that the debt for a borrower with good credit is more than $17,400?
b) What is the probability that the debt for a borrower with good credit is less than $10,500?
c) What is the probability that the debt for a borrower with good credit is between $12,000 and $18,000?
d) What is the probability that the debt for a borrower with good credit is no more than $13,500?