document.write( "Question 1184118: How much of a 60% orange juice drink must be mixed with 9 gallons of a 40% orange juice drink to obtain a mixture that is 50% orange juice?\r
\n" ); document.write( "\n" ); document.write( "The amount of 60% orange juice drink is x gallons.
\n" ); document.write( "(Type an integer or a decimal.)\r
\n" ); document.write( "\n" ); document.write( "Please help me find \"x\" thank you
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Algebra.Com's Answer #814678 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "This is mixing a weaker solution of OJ with a stronger solution of OJ and\r\n" );
document.write( "ending up with a medium strength solution of OJ.\r\n" );
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document.write( "You can do this one in your head.  Since 60% is just as much above 50% as\r\n" );
document.write( "40% is below 50%, you would mix the same amount of each.  So the answer\r\n" );
document.write( "should be 9 gallons.\r\n" );
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document.write( "But that's not really working it the way your teacher expects.  Most mixture\r\n" );
document.write( "problems can't be done in your head.  This one was special.  Let's do it as\r\n" );
document.write( "your teacher expects.\r\n" );
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document.write( "Most teachers suggest that you should make a chart with such word problems,\r\n" );
document.write( "at least until you get a little more proficient.  One column for the amounts\r\n" );
document.write( "of liquid, one for the percents, and for the third we multiply what's in the\r\n" );
document.write( "other two columns, to get the amount of pure substance contained in the two\r\n" );
document.write( "liquids.\r\n" );
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document.write( "                 |        | percent as |   gallons of      |\r\n" );
document.write( "                 | gallons|  a decimal | pure OJ contained |\r\n" );
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document.write( "weaker solution  |   x    |     0.6    |      0.6x         |  \r\n" );
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document.write( "stronger solution|   9    |     0.4    |    0.4(9)         |\r\n" );
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document.write( "medium-strength  |  x+9   |     0.5    |   0.5(x+9)        |\r\n" );
document.write( "       solution  |        |            |                   |\r\n" );
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document.write( "The equation comes from the last column\r\n" );
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document.write( "Remove the decimals by multiplying through by 10:\r\n" );
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document.write( "Distribute:\r\n" );
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document.write( "Just as we figured, 9 gallons of each.\r\n" );
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document.write( "Edwin

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