document.write( "Question 545080: soybean meal is 18% protein,cornmeal is 9% protein.How many pounds of each should be mixed together in order to get 360-lb mixture that is 17% protein \n" ); document.write( "

Algebra.Com's Answer #355413 by josmiceli(19441) $\"\"$ $\"About$

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Let $\"a\"$ = pounds of soybean meal needed
\n" ); document.write( "Let $\"b\"$ = pounds of cornmeal needed
\n" ); document.write( "given:
\n" ); document.write( "(1) $\"+a+%2B+b+=+360+\"$
\n" ); document.write( "(2) $\"+%28+.18a+%2B+.09b+%29+%2F+360+=++.17+\"$
\n" ); document.write( "--------------------------
\n" ); document.write( "(2) $\"+.18a+%2B+.09b+=+.17%2A360+\"$
\n" ); document.write( "(2) $\"+.18a+%2B+.09b+=+61.2+\"$
\n" ); document.write( "(2) $\"+18a+%2B+9b+=+6120+\"$
\n" ); document.write( "---------------------
\n" ); document.write( "Multiply both sides of (1) by $\"9\"$ ,
\n" ); document.write( "and subtract (1) from (2)
\n" ); document.write( "(2) $\"+18a+%2B+9b+=+6120+\"$
\n" ); document.write( "(1) $\"+-9a+-+9b+=+-3240+\"$
\n" ); document.write( " $\"+9a+=+2880+\"$
\n" ); document.write( " $\"+a+=+320+\"$
\n" ); document.write( "and, since
\n" ); document.write( "(1) $\"+a+%2B+b+=+360+\"$
\n" ); document.write( "(1) $\"+320+%2B+b+=+360+\"$
\n" ); document.write( "(1) $\"+b+=+40+\"$
\n" ); document.write( "320 pounds of soybean meal are needed
\n" ); document.write( "40 pounds of cornmeal are needed
\n" ); document.write( "check answer:
\n" ); document.write( "(2) $\"+%28+.18a+%2B+.09b+%29+%2F+360+=++.17+\"$
\n" ); document.write( "(2) $\"+%28+.18%2A320+%2B+.09%2A40+%29+%2F+360+=++.17+\"$
\n" ); document.write( "(2) $\"++57.6+%2B+3.6+=+.17%2A360+\"$
\n" ); document.write( "(2) $\"+61.2+=+61.2+\"$
\n" ); document.write( "OK \n" ); document.write( "

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