document.write( "Question 163159: Soybean meal is 14% protein; cornmeal is 7% protein. How many pounds of each should be mixed together in order to get 280-lb mixture that is 13% protein?
\n" ); document.write( "How many pounds of cornmeal should be in the mixture?
\n" ); document.write( "How many pounds of soybean meal should be in the mixture? \n" ); document.write( "

Algebra.Com's Answer #120230 by Fombitz(32388) $\"\"$ $\"About$

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Call the quantity of soybean S and cornmeal C.
\n" ); document.write( "Write the total weight equation.
\n" ); document.write( "1. $\"S%2BC=280\"$
\n" ); document.write( "Write the concentration equation.
\n" ); document.write( "2. $\"S%2A0.14%2BC%2A0.07=%28S%2BC%29%2A0.13\"$
\n" ); document.write( "2. $\"14S%2B7C=13%28280%29\"$
\n" ); document.write( "2. $\"14S%2B7C=3640\"$
\n" ); document.write( "Use eq. 1 to solve for S in terms of C and substitute into eq. 2,
\n" ); document.write( "1. $\"S%2BC=280\"$
\n" ); document.write( " $\"S=280-C\"$
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\n" ); document.write( "2. $\"14S%2B7C=3640\"$
\n" ); document.write( " $\"14%28280-C%29%2B7C=3640\"$
\n" ); document.write( " $\"3920-14C%2B7C=3640\"$
\n" ); document.write( " $\"-7C=-280\"$
\n" ); document.write( " $\"C=40\"$
\n" ); document.write( "From eq. 1,
\n" ); document.write( " $\"S=280-C\"$
\n" ); document.write( " $\"S=280-40\"$
\n" ); document.write( " $\"S=240\"$
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\n" ); document.write( "240 pounds of soybeans and 40 pounds of cornmeal. \n" ); document.write( "

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