document.write( "Question 159214This question is from textbook
\n" ); document.write( ": Soybean meal is 14% protein, cornmeal is 7% protein. How many pounds of each should be mixed together to get a 280 pound mixture that is 12% protein? \n" ); document.write( "
Algebra.Com's Answer #117349 by ptaylor(2198)\"\" \"About 
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Let x=amount of soybean meal needed
\n" ); document.write( "Then 280-x=amount of cornmeal needed\r
\n" ); document.write( "\n" ); document.write( "Now we know that the amount of pure protein in the soybean meal(0.14x) plus the amount of pure protein in the cornmeal(0.07(280-x)) has to equal the amount of pure protein in the final mixture(0.12*280). So, our equation to solve is:
\n" ); document.write( "0.14x+0.07(280-x)=0.12*280 get rid of parens and simplify
\n" ); document.write( "0.14x+19.6-0.07x=33.6 subtract 19.6 from each side
\n" ); document.write( "0.14x-0.07x+19.9-19.6=33.6-19.6 collect like terms
\n" ); document.write( "0.07x=14 divide each side by 0.07
\n" ); document.write( "x=200 lb-----------------------------------amount of soybean meal needed\r
\n" ); document.write( "\n" ); document.write( "280-x=280-200=80 lb----------------------amount of cornmeal needed\r
\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "200*0.14+80*0.07=280*0.12
\n" ); document.write( "28+5.6=33.6
\n" ); document.write( "33.6=33.6\r
\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor
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