<PRE><B>Question 1051788</B>
 Michelle is making hamburger, using 5lbs of ground beef that is 15% fat and 7lbs of ground beef that is 3% fat. What is total percentage of the fat in the mixture? 
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Equation::
fat + fat = fat
0.15*5 + 0.03*7 = (x/100)(12)
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15*5 + 3*7 = 12x
75 + 21 = 12x
12x = 96
x = 8%
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Cheers,
Stan H.
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