Question 1126174
x, volume of the 50% alcohol
600-x, volume of the 20% alcohol


{{{50x+20(600-x)=40*600}}}

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{{{50x+20*600-20x=40*600}}}

{{{30x=20*600}}}

{{{3x=2*600}}}

{{{highlight(x=400)}}}------400 mL of the 50% alcohol


{{{200}}}-----------------200 mL of the 20% alcohol