The table shows the percentage of the population not covered

The table shows the percentage of the population not covered by health insurance in selected states for the years 1990 and 1999.

State Idaho Illinois Michigan Montana New York

1990 15.1 10.9 9.4 14.0 12.1

1999 19.1 14.1 11.2 18.6 16.4

a. Draw a scatter plot showing the relationship between the percentage not covered by health insurance in 1990 and the percentage not covered in 1999. Use the 1990 percentage as the independent variable.

b. Use your scatter plot to develop a model relating the 1990 percentage to the 1999 percentage.

c. In Wyoming, 12.5% of the population were not covered by health insurance in 1990. Use your model to estimate the percentage who were covered in 1999.

d. The actual percentage for Wyoming in 1999 was 16.1. Is your model reasonable?

Solution