document.write( "Question 479291: A dehydrated patient needs a 8.15% saline IV. Unfortunately the hospital only has bags of 8% and 10% saline solutions. How many liters of each of these solutions should be mixed together to yield 4 liters of the desires concentration?\r
\n" ); document.write( "\n" ); document.write( "I don't know where to start. \n" ); document.write( "
Algebra.Com's Answer #328395 by stanbon(75887)\"\" \"About 
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A dehydrated patient needs a 8.15% saline IV. Unfortunately the hospital only has bags of 8% and 10% saline solutions. How many liters of each of these solutions should be mixed together to yield 4 liters of the desires concentration?
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\n" ); document.write( "Equation:
\n" ); document.write( "salt + salt = salt
\n" ); document.write( "0.08x + 0.10(4-x) = 0.0815*4
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\n" ); document.write( "0.08x + 0.40 - 0.10x = 0.0815*4
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\n" ); document.write( "Multiply thru by 10000 to get:
\n" ); document.write( "800x + 4000 - 1000x = 815*4
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\n" ); document.write( "-200x = -740
\n" ); document.write( "x = 3.7 liters (amt. of 8% solution needed)
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\n" ); document.write( "4-x = 4 - 3.7 = 0.3 liters (amt. of 10% solution needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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