document.write( "Question 433417: A nurse has a solution that is 25% alcohol and another that is 50% alcohol. How much if the 25% alcohol must she use to make 20 L of a solution that is 40% alcohol? \n" ); document.write( "
Algebra.Com's Answer #300438 by stanbon(75887)\"\" \"About 
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A nurse has a solution that is 25% alcohol and another that is 50% alcohol. How much of the 25% alcohol must she use to make 20 L of a solution that is 40% alcohol?
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\n" ); document.write( "Two-variable solution:
\n" ); document.write( "Quantity Eq: t + f = 20 L
\n" ); document.write( "Alcohol Eq:0.25t+0.50f = 0.40*20
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\n" ); document.write( "Multiply thru Quantity by 50
\n" ); document.write( "Multiply thru Alcohol by 100
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\n" ); document.write( "50t + 50f = 50*20
\n" ); document.write( "25t + 50f = 40*20
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\n" ); document.write( "Subtract and solve for \"t\":
\n" ); document.write( "25t = 10*20
\n" ); document.write( "t = 8 L (amt. of 25% solution needed)
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\n" ); document.write( "Cheers,
\n" ); document.write( "Stan H.
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