document.write( "Question 990480: a chemist has two soltions of H. One has a 40% concentration and the other has a 25% concentration. How many liters of each solution must be mixed to obtain 135 liters of a 37% solution? \n" ); document.write( "
Algebra.Com's Answer #610488 by ikleyn(52832)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "1. Never heard or saw this term  \"soltion of H\".\r
\n" ); document.write( "\n" ); document.write( "I understand that you wanted to write  \"solutions\"  instead of \"soltions\",  but again I never heard or saw the term  \"solution of H\".  I suspect that such thing do not exist. \r
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\n" ); document.write( "\n" ); document.write( "2. OK,  actually,  it doesn't matter.  We will talk about,  let say,  an abstract solution. \r
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\n" ); document.write( "\n" ); document.write( "Then you have the system of two linear equations in two unknowns  x  and  y  that are two unknowns volumes of the solutions in units of volume,  let say,  in liters\r
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\n" ); document.write( "\n" ); document.write( "\"system%28x+%2B+y+=+135%2C%0D%0A0.4%2Ax+%2B+0.25%2Ay+=+0.37%2A%28x%2By%29%29\",\r
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\n" ); document.write( "\n" ); document.write( "or \r
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\n" ); document.write( "\n" ); document.write( "\"system%28x+%2B+y+=+135%2C%0D%0A0.4%2Ax+%2B+0.25%2Ay+=+0.37%2A135%29\",\r
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\n" ); document.write( "\n" ); document.write( "or\r
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\n" ); document.write( "\n" ); document.write( "\"system%28x+%2B+y+=+135%2C%0D%0A0.4%2Ax+%2B+0.25%2Ay+=+49.95%29\".\r
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\n" ); document.write( "\n" ); document.write( "The first equation is the conservation law for the volume of liquid.
\n" ); document.write( "The second equation is the conservation law for the volume of solute.\r
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\n" ); document.write( "\n" ); document.write( "This is how to construct  (to make,  to write)  the system of equations.  It is the most important part in solving problems on mixtures and on solutions. \r
\n" ); document.write( "\n" ); document.write( "The rest is just techniques  (which is important, though).\r
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\n" ); document.write( "\n" ); document.write( "Try to solve the system yourself.  You may use the substitution method\r
\n" ); document.write( "\n" ); document.write( "(express   y = 135 -x  from the first equation,
\n" ); document.write( "substitute it into the second equation,
\n" ); document.write( "you will get the single equation for the unknown  x,
\n" ); document.write( "then solve this equation
\n" ); document.write( "and back substitute the found value of  x  into the first equation of the original system to get the solution for  y).\r
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\n" ); document.write( "\n" ); document.write( "Good luck!\r
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