document.write( "Question 515503: How many gallons of a 5% solution should be mixed with a 10% solution to obtain 50 gallons of a mixture that is 8%? \n" ); document.write( "

Algebra.Com's Answer #344039 by oberobic(2304) $\"\"$ $\"About$

You can put this solution on YOUR website!
You need to keep track of how much 'pure' stuff is involved.
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\n" ); document.write( "8% * 50 gallons = .08*50 = 4 gal of 'pure' stuff
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\n" ); document.write( "x = gallons of 5% solution
\n" ); document.write( "50-x = gallons of 10% solution
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\n" ); document.write( "5%*x + 10%*(50-x) = 4
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\n" ); document.write( ".05x + .10(50-x) = 4
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\n" ); document.write( "multiply by 100 to eliminate decimals.
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\n" ); document.write( "5x + 10(50-x) = 400
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\n" ); document.write( "5x +500 -10x = 400
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\n" ); document.write( "-5x = -100
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\n" ); document.write( "x = 20 gal of 5% solution
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\n" ); document.write( "50-x = 30 gal of 10% solution
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\n" ); document.write( "Check to be sure it is 50 gal of 8% solution.
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\n" ); document.write( "5% * 20 = 1 gal
\n" ); document.write( "10% * 30 = 3 gal
\n" ); document.write( "1+3 = 4 gal, which is what we need.
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\n" ); document.write( "Answer: Mix 20 gal. of 5% solution and 30 gal. of 10% solution to make 50 gal. of 8% solution.
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\n" ); document.write( "Done. \n" ); document.write( "

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