document.write( "Question 1175937: David and Moira are trying to bake a chocolate cake for Alexis’ birthday. They require 300g of
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Algebra.Com's Answer #801714 by ikleyn(52866) $\"\"$ $\"About$

You can put this solution on YOUR website!
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document.write( "Let x = amount (the mass in grams) of the 90% cocoa.\r\n" );
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document.write( "Then the mass of the 80% cocoa is  (300-x) grams.\r\n" );
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document.write( "After that, write the standard equation of conservation mass (the pure cocoa)\r\n" );
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document.write( "in the mixture before and after the mixing\r\n" );
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document.write( "    0.9x + 0.8(300-x) = 0.86*300.\r\n" );
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document.write( "From this equation\r\n" );
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document.write( "    x =  = 180.\r\n" );
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document.write( "ANSWER.  180 grams of the 90% cocoa and the rest, (300-180) = 120 grams of the 80% cocoa.\r\n" );
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document.write( "CHECK.  I will check the concentration   = 0.86 = 86%.    ! Precisely correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "In this site, there is entire bunch of lessons covering various types of mixture problems. \r
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\n" ); document.write( "\n" ); document.write( "Of them the most closest to your problem are\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
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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( "\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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