document.write( "Question 1112665: A 26-quart radiator contains 50% coolant solution. How much of the solution needs to be drained and replaced with pure coolant to obtain a 60% coolant solution? \n" ); document.write( "
Algebra.Com's Answer #727709 by ikleyn(52781)\"\" \"About 
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document.write( "Let V be the volume to drain off from 26 quarts of antifreeze.\r\n" );
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document.write( "Step 1:  Draining.  After draining,  you have 26-V quarts of the 50% antifreeze.\r\n" );
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document.write( "                    It contains 0.50*(26-V) of pure antifreeze.\r\n" );
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document.write( "Step 2:  Replacing.  Then you add V quarts of the pure antifreeze (the replacing step).\r\n" );
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document.write( "                     After the replacing,  you have the same total liquid volume of 26 quarts.\r\n" );
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document.write( "                     It contains 0.50*(26-V) + V quarts of pure antifreeze.\r\n" );
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document.write( "So, the antifreeze concentration after replacement is  \"%280.50%2A%2826-V%29%2BV%29%2F26\". \r\n" );
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document.write( "It is the ratio of the pure antifreeze volume to the total volume.\r\n" );
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document.write( "Therefore, your \"concentration equation\" is\r\n" );
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document.write( "\"%280.50%2A%2826-V%29%2BV%29%2F26\" = 0.6.    (1)    \r\n" );
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document.write( "The setup is done and completed.\r\n" );
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document.write( "To solve the equation (1), multiply both sides by 26. You will get\r\n" );
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document.write( "0.50*(26-V) + V= 0.6*26,\r\n" );
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document.write( "13 - 0.5V + V= 15.6,\r\n" );
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document.write( "0.5V = 15.6 - 13 = 2.6  ====>  V = \"2.6%2F0.5\" = 5.2 liters.\r\n" );
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document.write( "Answer.  5.2 quarts of the 50% antifreeze must be drained and replaced by 5.2 quarts of pure antifreeze.\r\n" );
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document.write( "Check.   \"%280.50%2A%2826-5.2%29%2B5.2%29%2F26\" = 0.6.    ! Correct !\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
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution mixture word problems.
\n" ); document.write( "Notice that among these lessons there is one on antifreeze solutions marked by (*).\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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