document.write( "Question 1114594: Mrs. Ernsthausen wants to create a sugar solution for her hummingbird feeder. She has a 20% sugar solution. She has learned that a 25% sugar solution is optimal. How many cups of pure sugar and 20% sugar solution does she need to mix together to make two cups of 25% sugar solution? \n" ); document.write( "

Algebra.Com's Answer #753162 by ikleyn(52787) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " This problem is posed incorrectly (or at least incompletely) in this post.\r
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\n" ); document.write( "\n" ); document.write( " Here I want to explain why it is incorrect (or at least incomplete).\r
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document.write( "First, the concentration of solutions in this problem is in grams per liter.\r\n" );
document.write( "Grams of sugar per liter of water.\r\n" );
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document.write( "It is not in cups of sugar per cup of water.\r\n" );
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document.write( "Also, the person who solves this problem, must know that the volumes are not added when a cup of sugar is dissolved in water.\r\n" );
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document.write( "These are elementary knowledge from Science that the student must possess when he starts solving the problems like this one.\r\n" );
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document.write( "So, to have the formulation complete, the density of the sugar in the cup must be given,\r\n" );
document.write( "and the primary unknown should be the mass of sugar, but not the number of cups of sugar.\r\n" );
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document.write( "Warning :  when you start solving a problem on mixtures and concentrations, the first thing you must clearly understand is\r\n" );
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document.write( "    in which units the concentration is measured / (is given) ?\r\n" );
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document.write( "It can be [volume-to-volume], [mass-to-mass] or [mass-to-volume].\r\n" );
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document.write( "All these things are clearly explained in my lessons\r\n" );
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document.write( "    - Mixture problems\r\n" );
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document.write( "    - More Mixture problems\r\n" );
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document.write( "in this site.\r\n" );
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document.write( "Again, these knowledge is the minimum student must possess about physics of solutions to solve such problems consciously.\r\n" );
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document.write( "There is no need to explain that the person who positions himself as a \"problems-creator\" or a \"tutor\" must know it perfectly.\r\n" );
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document.write( "This my post is addressed to the person who posted/created this problem, as well as to the tutor @VFBundy.\r\n" );
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