Question 1073416
x, amount of 30%
90-x, amount of 60%


{{{(30x+60(90-x))/90=50}}}


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{{{3x+6(90-x)=9*50}}}

{{{x+2(90-x)=3*50}}}

{{{x+180-2x=150}}}

{{{-x=150-180}}}

{{{highlight(x=30)}}} ----------volume of the 30%
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{{{highlight(90-x=60)}}}---------volume of the 60%