document.write( "Question 265884: How many gallons of 30% alcohol solution and 70% alcohol solution must be mixed to get 16 gallons of 60% solution? \n" ); document.write( "

Algebra.Com's Answer #195424 by vksarvepalli(154) $\"\"$ $\"About$

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let x gallons of 30% alcohol solution be taken\r
\n" ); document.write( "\n" ); document.write( "it contains 0.3x gallons of alcohol\r
\n" ); document.write( "\n" ); document.write( "let y gallons of 70% alcohol solution be taken\r
\n" ); document.write( "\n" ); document.write( "it contains 0.7x gallons of alcohol\r
\n" ); document.write( "\n" ); document.write( "now to get 16 gallons \r
\n" ); document.write( "\n" ); document.write( "x+y=16 ------------------ equation 1\r
\n" ); document.write( "\n" ); document.write( "and to have a 60% alcohol solution \r
\n" ); document.write( "\n" ); document.write( "the amount of alcohol must be 60% of 16 = 9.6 gallons\r
\n" ); document.write( "\n" ); document.write( "so 0.3x+0.7y = 9.6 ------------- equation 2\r
\n" ); document.write( "\n" ); document.write( "now multiply eq.1 by 0.3 and subtract it from eq.2\r
\n" ); document.write( "\n" ); document.write( "we get 0.4y = 4.8\r
\n" ); document.write( "\n" ); document.write( "so y=12\r
\n" ); document.write( "\n" ); document.write( "and x=4\r
\n" ); document.write( "\n" ); document.write( "So 4 gallons of 30% alcohol solution and 12 gallons of 70% alcohol solution should be mixed to get 16 gallons of 60% alcohol solution. \n" ); document.write( "

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