Question 1092486
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Let old price was P dollars per gallon.
Let old consumption was G gallons.


New price is 1.3*P.
New consumption is x gallons.


The equation is


1.3*P*x = P*G.     (1)


Hence,  x = {{{(P/(1.3*P))*G}}} = 0.769*G.


<U>Answer</U>.  New consumption must be  0.769*G,  or  {{{1/1.3}}} part of the old consumption.
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<U>Lesson to learn from this solution</U>:


<pre>
     Equation (1) - your basic equation.

     And also the logic behind this solution, which leads to equation (1).
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