Question 122334
<pre><big><b>
What you are looking for is a function that results in the value of change
based on the value of a purchase with the amount tendered a constant $20.


Let c be the amount of change, and we want {{{c=f(p)}}} where p is the
purchase amount.


{{{c=f(p)=20-p}}}


I'm not sure what your book means by a function table, unless it is a list of
values for the independent variable (p in this case) against the value of the
function at that point.  Here's a fragment of such a table:


<table border="1" cellpadding="10">
<tr>
<th>p</th>
<th>c</th>
</tr>
<tr>
<td>3.50</td>
<td>16.50</td>
</tr>
<tr>
<td>4.00</td>
<td>16.00</td>
</tr>
<tr>
<td>4.50</td>
<td>15.50</td>
</tr>
<tr>
<td>5.00</td>
<td>15.00</td>
</tr>
</table>






</pre></big></b>