document.write( "Question 412299: how many liters each of 15% acid solution and 33% acid solution should be mixed to get 120 L of 21% acid solution?\r
\n" ); document.write( "\n" ); document.write( "what i have so far.\r
\n" ); document.write( "\n" ); document.write( "liter of sol. percent liter of acid
\n" ); document.write( " x 15% .15 .15x
\n" ); document.write( " y 33% .33 .33y
\n" ); document.write( " 120 21% .21 .21(120)\r
\n" ); document.write( "\n" ); document.write( " \n" ); document.write( "
Algebra.Com's Answer #289615 by stanbon(75887)\"\" \"About 
You can put this solution on YOUR website!
how many liters each of 15% acid solution and 33% acid solution should be mixed to get 120 L of 21% acid solution?
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\n" ); document.write( "Equation:
\n" ); document.write( "acid + acid = acid
\n" ); document.write( "0.15x + 0.33(120-x) = 0.21*120
\n" ); document.write( "---
\n" ); document.write( "Multiply thru by 100 to get:
\n" ); document.write( "15x + 33*120 - 33x = 21*120
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\n" ); document.write( "-18x = -12*120
\n" ); document.write( "---
\n" ); document.write( "x = (2/3)*120
\n" ); document.write( "x = 80L (amt of 15% solution needed)
\n" ); document.write( "---
\n" ); document.write( "120-x = 40L (amt. of 33% solution needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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