In 2007, the average conventional first mortgage for new single-family homes was $360,000. Assuming a normal distribution and a standard deviation of σ = $30,000, what proportion of the mortgages were Source: Bureau of the Census, Statistical Abstract of the United States 2009, p. 726.
a. more than $360,000?
b. between $300,000 and $420,000?
c. between $330,000 and $390,000?
d. more than $270,000?