document.write( "Question 1101892: An industrialist has 450 litres of a chemical which is 70% pure. he mixes it with a chemical of the same type but 90% pure so as to obtain a mixture which is 75% . pure. find the amount of the 90% pure chemical used. \n" ); document.write( "

Algebra.Com's Answer #716506 by ikleyn(52879) $\"\"$ $\"About$

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\n" ); document.write( "an industrialist has 450 litres of a chemical which is 70% pure. he mixes it with a chemical of the same type but 90% pure
\n" ); document.write( "so as to obtain a mixture which is 75% . pure. find the amount of the 90% pure chemical used.
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document.write( "Let x be the volume of the 90% solution, in liters.\r\n" );
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document.write( "450 liters of the 70% solution contain 0.7*450 liters of the pure.\r\n" );
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document.write( "x   liters of the 90% solution contain 0.9*x liters   of the pure.\r\n" );
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document.write( "Final (450+x) liters solution contain  0.75*(450+x)  liters of the pure.\r\n" );
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document.write( "PURE    + PURE   = PURE           ========================>\r\n" );
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document.write( "0.7*450 + 0.9*x  =  0.75*(450+x) \r\n" );
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document.write( "You just got your balance equation for \"the pure\".\r\n" );
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document.write( "Now solve it:\r\n" );
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document.write( "0.7*450 + 0.9x = 0.75*450 + 0.75x  ====>\r\n" );
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document.write( "0.9x - 0.75x = 0.75*450 - 0.7*450,\r\n" );
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document.write( "0.15x = 0.05*450  ====>  x =  = 150.\r\n" );
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document.write( "Answer.  150 liters of the 90% solution should be added.\r\n" );
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document.write( "Check.  There are  0.7*450 + 0.9*150 = 450 liters of the pure in the input components.   \r\n" );
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document.write( "        There are  0.75*(450+150) = 450 liters of the pure in the FINAL solution.   ! Correct !\r\n" );
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\n" ); document.write( "\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( "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 the 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( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\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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