<PRE><B>Question 10885</B>
Let x = Number of miles driven in the city
627 - x = Number of miles driven on highway


The basic formula here is {{{ (Miles)/(MilesPerGallon) = Gallons}}}

Gallons in city + gallons on highway = Total gallons
{{{ x/22 + (627-x)/28 = 24}}}


Multiply both sides of the equation by the product of the two denominators:  {{{22*28}}}
{{{(22*28)* (x/22) + (22*28)*(627-x)/28 = 22*28*24}}}

{{{28x + 22(627-x) = 14784}}}

{{{28x + 13794-22x= 14784}}}
{{{6x = 14784-13794 = 990}}}
{{{x = 990/6 =165}}}  Miles in city
{{{627 - 165 = 462}}} Miles on highway


Total gas used:
{{{165/22 + 462/28 }}} gallons
{{{7.5 + 16.5 }}} gallons
{{{24}}} gallons total


R^2 at SCC 


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