document.write( "Question 1112590: e\r
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\n" ); document.write( "\n" ); document.write( "A chemical company makes two brands of antifreeze. The first brand is
\n" ); document.write( "65
\n" ); document.write( "%\r
\n" ); document.write( "\n" ); document.write( "pure antifreeze, and the second brand is
\n" ); document.write( "90
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\n" ); document.write( "\n" ); document.write( "pure antifreeze. In order to obtain
\n" ); document.write( "90\r
\n" ); document.write( "\n" ); document.write( "gallons of a mixture that contains
\n" ); document.write( "75
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\n" ); document.write( "\n" ); document.write( "pure antifreeze, how many gallons of each brand of antifreeze must be used? \n" ); document.write( "
Algebra.Com's Answer #727651 by ikleyn(52781)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "Let \"x\" the amount of the 65% antifreeze to be mixed, in gallons.\r\n" );
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document.write( "Then the amount of the 90% antifreeze is (90-x) gallons.\r\n" );
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document.write( "Your equation is\r\n" );
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document.write( "\"%280.65x+%2B+0.9%2A%2890-x%29%29%2F90\" = 0.75.\r\n" );
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document.write( "The numerator of this formula is the amount of the pure antifreeze in the mixture,\r\n" );
document.write( "that came from each of the two input solutions.\r\n" );
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document.write( "Divided by the total volume of 90 gallons, it is the concentration of the antifreeze in the mixture, \r\n" );
document.write( "which must be 0.75 = 75%, according to the problem requirement.\r\n" );
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document.write( "To solve the equation, multiply both sides by 90. You will get\r\n" );
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document.write( "0.65x + 0.9*90 - 0.9x = 0.75*90\r\n" );
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document.write( "-0.25x = 0.75*90 - 0.9*90 = -13.5  ====>  x = \"%28-13.5%29%2F%28-0.25%29\" = 54.\r\n" );
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document.write( "Answer.  54 gallons of the 65%  and (90-54) = 36 gallons of the 90% antifreeze should be mixed to get 90 gallons of the 75% antifreeze.\r\n" );
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document.write( "Check.   \"%280.65%2A54+%2B+0.9%2A36%29%2F90\" = 0.75 = 75%    ! 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
\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( "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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