document.write( "Question 704199: In a certain medical test designed to measure carbohydrate tolerance, an adult drinks 7 ounces of a 20% glucose solution. When the test is administered to a child, the glucose concentration must be decreased to 10%. How much 20% glucose solution and how much water should be used to prepare 7 ounces of 10% glucose solution?
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Algebra.Com's Answer #433972 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"+w+\"$ = ounces of water needed
\n" ); document.write( "Let $\"+x+\"$ = ounces of 20% glucose solution needed
\n" ); document.write( " $\"+.2x+\"$ = ounces of glucose in 20% solution
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+w+%2B+x+=+7+\"$
\n" ); document.write( "(2) $\"+.2x+%2F+%28+x+%2B+w+%29+=+.1+\"$
\n" ); document.write( "-----------------------
\n" ); document.write( "(2) $\"+.2x+=+.1%2A%28+x+%2B+w+%29+\"$
\n" ); document.write( "(2) $\"+.2x+=+.1x+%2B+.1w+\"$
\n" ); document.write( "(2) $\"+.1x+=+.1w+\"$
\n" ); document.write( "(2) $\"+x+=+w+\"$
\n" ); document.write( "So, I can say
\n" ); document.write( "(1) $\"+w+%2B+x+=+7+\"$
\n" ); document.write( "(1) $\"+2x+=+7+\"$
\n" ); document.write( "(1) $\"+x+=+3.5+\"$
\n" ); document.write( " $\"+w+=+3.5+\"$
\n" ); document.write( "3.5 ounces of water should be used
\n" ); document.write( "check:
\n" ); document.write( "(2) $\"+.2x+%2F+%28+x+%2B+w+%29+=+.1+\"$
\n" ); document.write( "(2) $\"+.2%2A3.5+%2F+%28+3.5+%2B+3.5+%29+=+.1+\"$
\n" ); document.write( "(2) $\"+.7+%2F+7+=+.1+\"$
\n" ); document.write( "(2) $\"+.7+=+.7+\"$
\n" ); document.write( "OK\r
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