document.write( "Question 1072131: You have 10 cups of a cleaning solution that is 10% white vinegar and 90% water. You want the mixture to be 20% white vinegar and 80% water. How many cups of white vinegar do you need to add to the mixture? \n" ); document.write( "
Algebra.Com's Answer #687014 by ikleyn(52781)\"\" \"About 
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\n" ); document.write( "You have 10 cups of a cleaning solution that is 10% white vinegar and 90% water. You want the mixture to be 20% white vinegar
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document.write( "Let x be the volume of white vinegar you need to add to the mixture (measured in cups).\r\n" );
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document.write( "Then the amount of the pure vinegar in the mixture will be (10*0.1 + x) cups.\r\n" );
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document.write( "The volume of liquid will be 10 + x.\r\n" );
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document.write( "The concentration equation is\r\n" );
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document.write( "\"%2810%2A0.1+%2B+x%29%2F%2810%2Bx%29\" = 0.2.\r\n" );
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document.write( "Multiply both sides by (10+x) and then simplify. You will get\r\n" );
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document.write( "1 + x = 0.2x + 2,\r\n" );
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document.write( "x - 0.2x = 2 - 1  --->  0.8x = 1  --->  x = \"1%2F0.8%7D%7D+=+%7B%7B%7B10%2F8\" = 1.25.\r\n" );
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document.write( "Answer.  you need to add 1.25 of a cup of the pure vinegar to the mixture.\r\n" );
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document.write( "Check.  \"0.1%2A10+%2B+1.25%29%2F%2810%2B1.25%29\" = \"2.25%2F11.25\" = 0.2.  Correct !\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "The solution by \"josgarithmetic is WRONG. \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
\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 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\n" ); document.write( "
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