document.write( "Question 1147676: 9 Kg. of gold which is 80% pure is mixed with an unknown amount of gold which is 75% pure. The purity of the resulting mixture is 78%. What quantity of the second type of gold was added?
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Algebra.Com's Answer #769024 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Your basic equation is THIS :\r\n" );
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document.write( "    0.8*9 + 0.75*x = 0.78*(x+9)\r\n" );
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document.write( "From it, express x and calculate\r\n" );
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document.write( "    x = \"%280.78%2A9-0.8%2A9%29%2F%280.75-0.79%29\" = 4.5.\r\n" );
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document.write( "ANSWER.  4.5 kg of the second alloy should be added.\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 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
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\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( "    - Advanced mixture problems \r
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\n" ); document.write( "\n" ); document.write( "You will find there ALL TYPICAL mixture problems with different methods of solutions,
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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 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
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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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