document.write( "Question 305557: How many gallons of a 3% salt solution must be mixed with a 7% salt solution to obtain 100 gallons of a 5% salt solution?
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Algebra.Com's Answer #218785 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "Let

represent the number of gallons of 3% solution. Then the gallons of pure salt in the 3% solution must be

. The number of gallons of 7% solution, given that we need 100 gallons overall, must be

, and the number of gallons of pure salt in the 7% solution must be

. And finally, there has to be 5 gallons of pure salt in 100 gallons of 5% solution.\r
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\n" ); document.write( "\n" ); document.write( "If you multiply by 100 you get integer coefficients -- much neater:\r
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\n" ); document.write( "\n" ); document.write( "Just solve for

.\r
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