Question 1166486
<pre>
CONCENTRATION%       VOLUME         PURE Acid

   15                 x             0.15x

   60                 j             0.6(3x+3y-30)

   75                 y            0.75y

   51                 100          0.51*100
</pre>


This part seems unclear: "If the sum of three times the number of gallons of a 15% acid and a 75% acid is thirty more than the number of gallons of 60% acid"


{{{3x+3y=j+30}}}
{{{j=3x+3y-30}}}

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