document.write( "Question 750796: How many liters of a 7% solution of salt should be added to a 27% solution in order to obtain 780 liters of a 13% solution?
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Algebra.Com's Answer #456788 by josgarithmetic(39617) $\"\"$ $\"About$

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(amount of acid)/(amount of mixture)=fraction as the acid or the concentration\r
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\n" ); document.write( "\n" ); document.write( "Some parts are variable.\r
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\n" ); document.write( "\n" ); document.write( "Let u = liters volume to add of the 7% acid.
\n" ); document.write( "Let v = liters of 27% acid.\r
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\n" ); document.write( "\n" ); document.write( "Amount of acid = u*7%+v*27%
\n" ); document.write( " $\"%287u%2B27v%29%2F780=13\"$ and $\"u%2Bv=780\"$
\n" ); document.write( "Although one of these is rational equation, they both are linear equations in two variables.
\n" ); document.write( "Just solve the system for u and v. \n" ); document.write( "

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