document.write( "Question 150550: Soybean meal is 14% protein; cornmeal is 7% protein. How many lbs of each should be mixed together in order to
\n" ); document.write( "get 280-lb mixture that is 10% protein?
\n" ); document.write( "How many pounds of the cornmeal should be in the mixture?
\n" ); document.write( "How many pounds of soybean should be in the mixture? \n" ); document.write( "

Algebra.Com's Answer #110511 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Let $\"s\"$ = lbs of soybean meal to be used
\n" ); document.write( "Let $\"c\"$ = lbs of cornmeal to be used
\n" ); document.write( "Protein in the soybean meal = $\".14s\"$
\n" ); document.write( "Protein in the cornmeal = $\".07c\"$
\n" ); document.write( "In words:
\n" ); document.write( "(total lbs of protein in mixture) / (lbs of mixture) = % protein
\n" ); document.write( " $\"%28.14s+%2B+.07c%29+%2F+280+=+.1\"$
\n" ); document.write( "multiply both sides by $\"280\"$
\n" ); document.write( "(1) $\".14s+%2B+.07c+=+28\"$
\n" ); document.write( "Also known is $\"s+%2B+c+=+280\"$
\n" ); document.write( "Multiply both sides by $\".14\"$
\n" ); document.write( "(2) $\".14s+%2B+.14c+=+39.2\"$
\n" ); document.write( "Subtract (1) from (2)
\n" ); document.write( " $\".07c+=+11.2\"$
\n" ); document.write( " $\"c+=+160\"$ lbs
\n" ); document.write( "And since $\"s+%2B+c+=+280\"$
\n" ); document.write( " $\"s+%2B+160+=+280\"$
\n" ); document.write( " $\"s+=+120\"$ lbs
\n" ); document.write( "160 lbs of cornmeal are needed and 120 lbs of soybean meal are needed
\n" ); document.write( "check:
\n" ); document.write( " $\"%28.14s+%2B+.07c%29+%2F+280+=+.1\"$
\n" ); document.write( " $\"%28.14%2A120+%2B+.07%2A160%29+%2F+280+=+.1\"$
\n" ); document.write( " $\"%2816.8+%2B+11.2%29+%2F+280+=+.1\"$
\n" ); document.write( " $\"28+%2F+280+=+.1\"$
\n" ); document.write( " $\"28+=+28\"$
\n" ); document.write( "OK \n" ); document.write( "

\n" );