document.write( "Question 1136765: To make a 6% acid solution, a chemist mixes some 4% acid solution with 12 L of 10% acid solution. How much of the 4% solution must be added to the 10% solution to make the 6% acid solution?\r
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\n" ); document.write( "\n" ); document.write( "I'm guessing that I need to make x=4% but I'm not sure what I need to use for the other variable. \n" ); document.write( "
Algebra.Com's Answer #754569 by rothauserc(4718)\"\" \"About 
You can put this solution on YOUR website!
Let x be the amount of the 4% solution needed to mix with the 10% solution to get a 6% solution
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\n" ); document.write( "There are three relations to consider, the third relation is the mixture
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\n" ); document.write( "1) 12 * 0.10 = 1.20 L of acid
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\n" ); document.write( "2) x * 0.04 = 0.04x L of acid
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\n" ); document.write( "3) (x+12) * 0.06 = 0.06(x+12)
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\n" ); document.write( "1.20 +0.04x = 0.06(x+12)
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\n" ); document.write( "1.20 +0.04x = 0.06x +0.72
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\n" ); document.write( "0.02x = 0.48
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\n" ); document.write( "x = 24
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\n" ); document.write( "The chemist needs 24 L of the 4% solution to make a 6% solution
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