document.write( "Question 835031: What is the final salt concentration if 20kg of a solution containing 21 percent (m/m) salt is mixed with 10kg of a solution containing 12 percent (m/m) salt?\r
\n" ); document.write( "\n" ); document.write( "salt mass= 20kg x .21 kg/kg + 10kg x.12kg/kg= 4.2 kg + 1.2kg= 5.4 kg
\n" ); document.write( "total solution mass= 20 kg+ 10 kg= 30 kg\r
\n" ); document.write( "\n" ); document.write( "How do I calculate the final concentration? \n" ); document.write( "
Algebra.Com's Answer #503306 by Theo(13342)\"\" \"About 
You can put this solution on YOUR website!
you let x equal the concentration of salt in the final solution.
\n" ); document.write( "your formula becomes:\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( ".21(20) + .12(10) = x(30)
\n" ); document.write( "this equation becomes:
\n" ); document.write( "4.2 + 1.2 = x(30)
\n" ); document.write( "this simplifies to:
\n" ); document.write( "5.6 = x(30)
\n" ); document.write( "divide both sides of this equation by 30 to get:
\n" ); document.write( "x = 5.6/30 = .1867 rounded to the fourth decimal digit.
\n" ); document.write( "confirm by multiplying 30 * .1867.
\n" ); document.write( "you should get something close to 5.6.
\n" ); document.write( "you'll get much closer or right on if you don't round.
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