document.write( "Question 649609: A Biologist mixes a 15% salt solution with a 35% salt solution to create 20 mL of a 22% salt solution.Which equation can you use to find the amount of 15% salt solution that is used? \n" ); document.write( "
Algebra.Com's Answer #407011 by ptaylor(2198)\"\" \"About 
You can put this solution on YOUR website!
Let x=amount of 15% salt solution that is used
\n" ); document.write( "Then 20-x=amount of 35% salt solution that is used
\n" ); document.write( "Now we know that the amount of pure salt that exists before the mixture takes place (0.15x+0.35(20-x)) has to equal the amount of pure salt that exists after the mixture takes place (0.22*20). Soooooo:
\n" ); document.write( "0.15x+0.35(20-x)=0.22*20 Now if we solve this equation for x, we get the amount of 15% salt solution that is used.\r
\n" ); document.write( "\n" ); document.write( "SO, LET'S DO IT!
\n" ); document.write( "Simplifying, we get:
\n" ); document.write( "0.15x+7-0.35x=4.4 subtract 7 from each side
\n" ); document.write( "-0.20x=-2.6
\n" ); document.write( "x=13 mL----amount of 15% salt solution that is used\r
\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "0.15*13+0.35*7=4.4
\n" ); document.write( "1.95+2.45=4.4
\n" ); document.write( "4.4=4.4\r
\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor\r
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