City planners believe that larger cities are populated by older residents. To investigate the relationship, data on population and median age in 10 large cities were collected.

a. Plot these data on a scatter diagram with median age as the dependent variable.
b. Find the correlation coefficient.
c. A regression analysis was performed and the resulting regression equation is Median Age 5 31.4 1 0.272 Population. Interpret the meaning of the slope.
d. Estimate the median age for a city of 2.5 million people.
e. Here is a portion of the regression software output. What does it tell you?

f. Using the .10 significance level, test the significance of the slope. Interpret the result. Is there a significant relationship between the twovariables?