<PRE><B>Question 412152</B>
Let x= number of quarts of 6% buttermilk
y= number of quarts of 3% buttermilk
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EQ 1
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{{{x+y=45}}} 
Multiply 0.03 by EQ (1)
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{{{0.03*x+0.03*y=45(0.03)}}}
{{{0.03x+0.03y=1.35}}}

__________
EQ 2
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{{{0.06x+0.03y=0.05(45)}}} ----(Simplfy this EQ 2)
{{{0.06x+0.03y=2.25}}}

Therefore 
{{{0.03x+0.03y=1.35}}} (Eq 1)
{{{0.06x+0.03y=2.25}}} (Eq 2)
Subtract (Eq 1) from (Eq 2)
{{{    0.03y=0.90}}}
{{{     y= 30}}}
{{{x+30=45}}}
{{{x=15}}}

15 quarts of 6% buttermilk are mixed with 15 quarts of 3% buttermilk.






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