<PRE><B>Question 842352</B>
Uniform rates problem for fuel efficiency.
{{{highlight_green(R*v=d)}}}, R rate, v volume of fuel, d distance.
The unit of rate R is kilometers per liter.



_________________fuel effic.________volume_________distance
CITY_____________6.5/100______________()____________()__________
HIGHWAY__________5.5/100______________()____________()__________
TOTAL________________________________40______________650



Some missing information needs to be formulated.  Assign two variables, EITHER for volumes, OR for distances.  Here is my arbitrary choice:


_________________fuel effic.________volume_________distance
CITY_____________6.5/100______________(c)____________()______
HIGHWAY__________5.5/100______________(h)____________()______
TOTAL_________________________________40______________650



Use your fuel efficiency equation rule to make expressions for the distances.


_________________fuel effic.________volume_________distance
CITY_____________6.5/100______________(c)____________((6.5/100)c)
HIGHWAY__________5.5/100______________(h)____________((5.5/100)h)
TOTAL_________________________________40______________650


The table now indicates two linear equations in the variables c and h.
SYSTEM TO SOLVE
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{{{(6.5/100)c+(5.5/100)h=650}}}
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{{{c+h=40}}}
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The remaining arithmetic steps are for you to do. (Start by multiplying left and right sides of the distance equation by 200.)</PRE>