Question 335595
Let A be the amount of feed A, B the amount of feed B.
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Total weight equation
1.{{{A+B=450}}}
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Concentration equation
{{{18A+10B=15(450)}}}
{{{18A+10B=6750}}}
2.{{{9A+5B=3375}}}
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From eq. 1,
{{{A=450-B}}}
Substitute into eq. 2,
{{{9(450-B)+5B=3375}}}
{{{4050-9B+5B=3375}}}
{{{-4B=-675}}}
{{{B=675/4}}}
Then from eq. 1,
{{{A+B=450}}}
{{{A+675/4=1800/4}}}
{{{A=1125/4}}}
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To the nearest pound,
A=281 lbs
B=169 lbs