For borrowers with good credit scores, the mean debt for revolving and installment

accounts is $15,015 (BusinessWeek, March 20, 2006). Assume the standard deviation is

$3540 and that debt amounts are normally distributed.

b. What is the probability that the debt for a borrower with good credit is less than

$10,000?

c. What is the probability that the debt for a borrower with good credit is between $12,000

and $18,000?