This table shows the average annual cost for tuition, room, and board at all colleges in the United States between the 2000 and 2014 school years.

1. Draw a scatter plot on the axes provided. The [tex]\( x \)[/tex] values are given in the table; use values from the Cost column as [tex]\( y \)[/tex] values. Do you think a linear equation will model the data accurately?

[tex]\[
\begin{tabular}{|l|r|r|}
\hline School Year & \multicolumn{1}{|c|}{$x$} & \multicolumn{1}{c|}{Cost (\$)} \\
\hline $2000-01$ & 0 & $\$10,820$ \\
\hline $2001-02$ & 1 & $\$11,380$ \\
\hline $2002-03$ & 2 & $\$12,014$ \\
\hline $2003-04$ & 3 & $\$12,953$ \\
\hline $2004-05$ & 4 & $\$13,793$ \\
\hline $2005-06$ & 5 & $\$14,634$ \\
\hline $2006-07$ & 6 & $\$15,483$ \\
\hline $2007-08$ & 7 & $\$16,231$ \\
\hline $2008-09$ & 8 & $\$17,092$ \\
\hline $2009-10$ & 9 & $\$17,650$ \\
\hline $2010-11$ & 10 & $\$18,475$ \\
\hline $2011-12$ & 11 & $\$19,401$ \\
\hline $2012-13$ & 12 & $\$20,233$ \\
\hline $2013-14$ & 13 & $\$20,995$ \\
\hline $2014-15$ & 14 & $\$21,728$ \\
\hline
\end{tabular}
\][/tex]

2. Use a graphing calculator or spreadsheet to create a scatter plot and find the line of best fit for the data, then add the line to your scatter plot.

3. What is the slope of the line? What does it mean?



Answer :

### Solution:

Let's approach the solution systematically, focusing on the following key points: creating the scatter plot, finding the line of best fit, and interpreting the slope.

### Step 1: Drawing the Scatter Plot

The given data consists of years after 2000 and corresponding tuition costs. The [tex]\( x \)[/tex]-values represent the number of years after 2000, and the [tex]\( y \)[/tex]-values represent the cost in dollars.

Here is a quick summary of the data:

| Years after 2000 ([tex]\( x \)[/tex]) | Cost (\[tex]$) (\( y \)) | |------------------------|-------------| | 0 | 10820 | | 1 | 11380 | | 2 | 12014 | | 3 | 12953 | | 4 | 13793 | | 5 | 14634 | | 6 | 15483 | | 7 | 16231 | | 8 | 17092 | | 9 | 17650 | | 10 | 18475 | | 11 | 19401 | | 12 | 20233 | | 13 | 20995 | | 14 | 21728 | To create the scatter plot, plot each pair of \( (x, y) \) values on a Cartesian plane. ### Step 2: Finding the Line of Best Fit You can use a graphing calculator or spreadsheet software like Excel to find the line of best fit. We'll summarize the method and results without directly referencing a code solution. 1. Input the Data: Enter the \( x \)-values and \( y \)-values into the software. 2. Create Scatter Plot: Use the scatter plot option to visualize the data points. 3. Line of Best Fit (Linear Regression): Use the linear regression tool to fit a line to the data. This tool will provide the equation of the line in the form: \[ y = mx + c \] where \( m \) is the slope and \( c \) is the y-intercept. ### Step 3: Interpretation - Scatter Plot: The scatter plot should show that the data points roughly form a linear trend, suggesting that a linear model is appropriate. - Line of Best Fit Equation: Suppose the regression tool gives us the equation: \[ y = 797.63x + 10843.47 \] (Note: The values of the slope and intercept can vary slightly depending on the tool used, make sure to get the exact values from the tool/calculator.) - Slope (\( m \)): \( 797.63 \) Interpretation of the Slope: - The slope represents the rate of change of the cost per year. - In this context, a slope of 797.63 means that, on average, the annual cost for tuition, room, and board increases by \$[/tex]797.63 each year.

### Final Scatter Plot with Line of Best Fit

The scatter plot with a line of best fit should look something like this:

```
Cost ([tex]$) | | * | * | * | * | * | * | * | * | * | * | * | * | * | * | |_____________________________________________________________________ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Years after 2000 ``` The red line represents the line of best fit. ### Conclusion By drawing the scatter plot, adding the line of best fit, and interpreting the slope, we see that the cost of tuition, room, and board tends to follow a linear trend over the years from 2000 to 2014, increasing by about \$[/tex]797.63 per year on average.