document.write( "Question 1103821: A mixture of 8% disinfectant solution is to be made from 12% and 5% disinfectant solutions. How much of each solution should be used if 63 gallons of 8% solution are needed?
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Algebra.Com's Answer #718510 by ikleyn(52787) $\"\"$ $\"About$

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document.write( "     x +      y = 63,         (1)   (total volume)\r\n" );
document.write( "0.12*x + 0.05*y = 0.08*63.    (2)   (pure disinfectant)\r\n" );
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document.write( "Multiply eq(1) by 0.05.  The modified system is\r\n" );
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document.write( "0.05*x + 0.05y = 0.05*63,     (3)  \r\n" );
document.write( "0.12*x + 0.05*y = 0.08*63.    (4)  \r\n" );
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document.write( "From eq(4) subtract eq(3). The terms \"0.05*y\" will cancel each other, and you will get\r\n" );
document.write( "a single equation for only one unknown x.   (It is how the Elimination method works).\r\n" );
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document.write( "0.012x - 0.05x = 0.08*63 - 0.05*63\r\n" );
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document.write( "0.07x = 0.03*63  ====>  x =  = 3*9 = 27.\r\n" );
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document.write( "Answer.  27 gallons of the 12% disinfectant  and  (63-27) = 36 gallons of the 5% disinfectant.\r\n" );
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\n" ); document.write( "There is entire bunch of introductory lessons covering various types of mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - More Mixture problems\r
\n" ); document.write( "\n" ); document.write( "    - Solving typical word problems on mixtures for solutions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for antifreeze solutions \r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for alloys \r
\n" ); document.write( "\n" ); document.write( "    - Typical word problems on mixtures from the archive\r
\n" ); document.write( "\n" ); document.write( "in this site.\r
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\n" ); document.write( "\n" ); document.write( "You will find there ALL TYPICAL mixture problems with different methods of solutions,
\n" ); document.write( "explained at different levels of detalization, from very detailed to very short.\r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution mixture word problems.\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lessons are the part of this textbook in the section \"Word problems\" under the topic \"Mixture problems\".\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
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\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I
\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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