The following table shows the percent increase of donations made on behalf of a non-profit organization for the period of 1984 to 2003. use a graphing calculator to make a scatter plot of the data. find an equation for and graph the line of regression. then use the equation to predict the percent donated in the year 2015.

Giving the table below which shows the percent increase of donations made on behalf of a non-profit organization for the period of 1984 to 2003.

Year:        1984     1989     1993     1997     2001     2003

Percent:    7.8       16.3       26.2      38.9     49.2      62.1

The scatter plot of the data is attached with the x-axis representing the number of years after 1980 and the y-axis representing the percent increase of donations made on behalf of a non-profit organization.

To find the equation for the line of regression where the x-axis representing the number of years after 1980 and the y-axis representing the percent increase of donations made on behalf of a non-profit organization.


Recall that the equation of the regression line is given by

where

and


Thus, the equation of the regresson line is given by


The graph of the regression line is attached.

Using the equation, we can predict the percent donated in the year 2015. Recall that 2015 is 35 years after 1980. Thus x = 35.

The percent donated in the year 2015 is given by


Therefore, the percent donated in the year 2015 is predicted to be 90.5