Question 102426
Juan has coffee that sells for $9 a pound and $4 a pound. How many pounds of each must be mixed to get 20 pounds of coffee worth $8.25 a pound? 
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Let amt. of $9 coffee be "x" ; Value of this is 9x dollars
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Amt. of $4 coffee is "20-x" ; value of this is 4(20-x)= 80-4x dollars
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Amt of mixture = 20 lbs ; value of this is 8.25*20 = 165 dollars
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EQUATION:
value + value = value
9x + 80-4x = 165
5x = 85
x =17 lbs (amount of $9 coffee in the mixture)
20-x = 3 lbs (amount of $4 coffee in the misture)


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Cheers,
Stan H.