document.write( "Question 1135490: A pharmacist is mixing an 4.7% saline solution and an 19% saline solution to get 3.2 litres of a 8.6% solution. How much of the 19% solution is needed?
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Algebra.Com's Answer #753100 by ikleyn(52788)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "There are several ways to solve it.\r\n" );
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document.write( "One way is to solve the system of 2 equations\r\n" );
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document.write( "       x +     y = 3.2     for the total volume of two solutions (in liters)   (1)\r\n" );
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document.write( "  0.047x + 0.19y = 0.086*3.2   for the mass of salt (in kilograms)             (2)\r\n" );
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document.write( "You may use the Elimination method. For it, multiply eq(1) by 0.047 (both sides). Keep eq(2) as is. You will get\r\n" );
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document.write( "   0.047x + 0.047y = 0.047*3.2    (3)\r\n" );
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document.write( "   0.047x + 0.19y  = 0.086*3.2    (4)    ( same as (2) )\r\n" );
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document.write( "Now subtract eq(3) from eq(4). You will get\r\n" );
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document.write( "            (0.19y - 0.047y) = 0.086*3.2 - 0.047*3.2\r\n" );
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document.write( "which gives you  y =  \"%280.086%2A3.2+-+0.047%2A3.2%29%2F%280.19+-+0.047%29\".\r\n" );
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document.write( "Now I copy this formula in MS Excel in my computer and get the answer in one click:  y = 0.873.\r\n" );
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document.write( "Then from eq(1),  x = 3.2 - 0.873 = 2.327.\r\n" );
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document.write( "Answer.  2.327 liters of the 4.7% solution and  0.873 liters of the 19% solution.\r\n" );
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\n" ); document.write( "\n" ); document.write( "        Notice that in the course of my solution I didn't make intermediate calculations.\r
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\n" ); document.write( "\n" ); document.write( "        It is simply in order for do not spend my efforts for nothing.\r
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\n" ); document.write( "\n" ); document.write( "        Instead, I collected everything into the final formula.\r
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\n" ); document.write( "\n" ); document.write( "        Then my MS Excel gave me the answer in one click.\r
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\n" ); document.write( "\n" ); document.write( "It is a standard and typical mixture problem.\r
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\n" ); document.write( "\n" ); document.write( "For introductory lessons covering various types of mixture word problems see\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( "    - 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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