The file /home/stone/courses/scheme/Iowa-cities.dat contains information about the sixty largest cities and towns in Iowa: their names and populations, as determined by the 1990 and 1980 censuses. A typical line of the file looks like this:
Grinnell 8902 8868
Columns 1 through 16 contain the name of the town, left-justified; columns 17 through 22 contain the 1990 population, right-justified; columns 23 and 24 are always spaces; and columns 25 through 30 contain the 1980 population, right-justified.
Write a Scheme program to answer the following questions, Using the data in the file just described.
What were the ten largest cities in Iowa in 1990?
How many cities in Iowa were larger than Grinnell in 1990?
The 1990 census population of the state of Iowa was 2829252. How many Iowans lived outside the sixty largest cities and towns in 1990?
What ten Iowa cities had the largest percentage decreases in population between 1980 and 1990?
Which of these sixty cities had the smallest percentage change in population (in either direction) between 1980 and 1990?
This document is available on the World Wide Web as
created April 26, 1998
last revised April 26, 1998
John David Stone (firstname.lastname@example.org)