Customer database. A large philanthropic organization keeps records on the people who have contributed to their cause. In addition to keeping records of past giving, the organization buys demographic data on neighborhoods from the U.S. Census Bureau. Eighteen of these variables concern the ethnicity of the neighborhood of the donor.

Here are a histogram and summary statistics for the percentage of whites in the neighborhoods of 500 donors:

d) What percentage of neighborhoods actually have a percent white within one standard deviation of the mean?

e) Explain the discrepancy between parts c and d.