document.write( "Question 1144544: You need a 65% alcohol solution. On hand, you have a 15 mL of a 25% alcohol mixture. You also have 70% alcohol mixture. How much of the 70% mixture will you need to add to obtain the desired solution? \n" ); document.write( "
Algebra.Com's Answer #765691 by ikleyn(52803)\"\" \"About 
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document.write( "Let x = the amount of the 70%  alcohol needed (in milliliters.\r\n" );
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document.write( "Then the amount of the resulting 65%  alcohol solution will be is (x+15) milliliters.\r\n" );
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document.write( "The amount of the \"pure\" alcohol in 15 mL of the 25% alcohol solution is 0.25*15 mL.\r\n" );
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document.write( "The amount of the \"pure\" alcohol in x mL of the 70% alcohol solution is 0.70*x mL.\r\n" );
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document.write( "The total amount of the \"pure\" alcohol in ingredients is the sum 0.25*15 + 0.70*x mL.\r\n" );
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document.write( "It should be equal to the amount of the \"pure\" alcohol in the mixture, which is 0.65*(x+15) ml.\r\n" );
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document.write( "So, your \"pure alcohol\" equation is \r\n" );
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document.write( "   0.70*x + 0.25*15 = 0.65*(x+15).\r\n" );
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document.write( "Simplify and solve it for x:\r\n" );
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document.write( "    0.70x + 0.25*15 =  0.65x + 0.65*15,\r\n" );
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document.write( "    0.70x - 0.65x = 0.65*15 - 0.25*15,\r\n" );
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document.write( "    0.05x = 6,\r\n" );
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document.write( "    x = \"6%2F0.05\" = 120.\r\n" );
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document.write( "Answer. 120 mL of 70% alcohol solution are needed.\r\n" );
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document.write( "Check.  0.07*120 + 0.25*15 = 87.5 mL of the pure alcohol in ingredients, and\r\n" );
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document.write( "        0.65*(120+15) = 87.75 mL of the pure alcohol in the final mixture.   ! Precisely 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( "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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