document.write( "Question 1161215: Pure acid is to be added to a 10% acid solution to obtain 99L of a 20% acid solution
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Algebra.Com's Answer #784719 by ikleyn(52787)\"\" \"About 
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document.write( "Let x be the amount of the pure acid to add in order for to get 99L of a 20% solution.\r\n" );
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document.write( "It means that the amount of the 10% original acid was  99-x liters.\r\n" );
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document.write( "The equation to find x is THIS\r\n" );
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document.write( "    0.1*(99-x) + x = 0.2*99.    (1)\r\n" );
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document.write( "It says that the amount of the pure acid in ingredients (left side) is the same as in the mixture (right side).\r\n" );
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document.write( "Simplify and solve the equation\r\n" );
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document.write( "    0.1*99 - 0.1x +x = 19.8\r\n" );
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document.write( "    0.9x = 19.8 - 0.1*99\r\n" );
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document.write( "    0.9x = 9.9\r\n" );
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document.write( "       x = \"9.9%2F0.9\" = 11.\r\n" );
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document.write( "ANSWER.  11 liters of the pure acid to add.\r\n" );
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document.write( "CHECK.   I will check equation (1).\r\n" );
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document.write( "         Ingredients:  0.1*(99-11) + 11 = 0.1*88 + 11 = 8.8+11 = 19.8  liters of the pure acid.\r\n" );
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document.write( "         Mixture:  0.2*99 = 19.8 liters of the pure acid.\r\n" );
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document.write( "         Both sides of the equation are equal.  The check is completed.\r\n" );
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\n" ); document.write( "\n" ); document.write( "It is a standard and typical mixture word problem. \r
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\n" ); document.write( "\n" ); document.write( "There is entire bunch of lessons in this site 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 dry substances like coffee beans, nuts, cashew and peanuts\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for dry substances like candies, dried fruits\r
\n" ); document.write( "\n" ); document.write( "    - Word problems on mixtures for dry substances like soil and sand\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( "    - Advanced mixture problems \r
\n" ); document.write( "\n" ); document.write( "    - Advanced mixture problem for three alloys \r
\n" ); document.write( "\n" ); document.write( "    - Unusual word problem on mixtures \r
\n" ); document.write( "\n" ); document.write( "    - Check if you know the basics of mixtures from Science \r
\n" ); document.write( "\n" ); document.write( "    - OVERVIEW of lessons on word problems for mixtures\r
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\n" ); document.write( "\n" ); document.write( "A convenient place to quickly observe these lessons from a  \"bird flight height\"  (a top view)  is the last lesson in the list.\r
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\n" ); document.write( "\n" ); document.write( "Read them and become an expert in solution the 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 online textbook 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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