<PRE><B>Question 313035</B>
Soybea meal is 12% protein, cornmeal is 6 % protein. How many pounds of each should be mixed in order to get a 240lb mixture that is 8%?

Let S be the amount of soybeans, C the amount of cornmeal.
1.{{{S+C=240}}}
2.{{{12S+6C=8(240)}}}
Multiply eq. 1 by (-6) and add the equations together.
{{{-6S-6C+12S+6C=-6(240)+8(240)}}}
{{{6S=2(240)}}}
{{{S=240/3=80}}}
Then from eq. 1,
{{{S+C=240}}}
{{{80+C=240}}}
{{{C=160}}}
80 lbs of soybeans, 160 lbs of cornmeal
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