Question 1101169
{{{PRICE*VOLUME=COST}}},  {{{basic}}}{{{idea}}}


<pre>
             PRICE   GALLONS  COST(dollars)
REGULAR       p       5       5p
PREMIUM      p+0.18   10     10(p+0.18)
Total                 15      31.05
</pre>

{{{5p+(10p+1.8)=31.05}}}
{{{15p+1.8=31.05}}}
{{{highlight(p=1.95)}}}---------price per gallon for regular
-
{{{p+0.18=highlight(2.13)}}}------price for premium