Question 760158
The manager of a bulk foods establishment sells a trail mix for $8 per
pound and premium cashews for $15 per pound. The manager wishes to
make a 105-pound trail mix-cashew mixture that will sell for $12 per
pound. How many pounds of each should be used? 
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Quantity Equation: t + c = 105 lb.
Value Equation:   8t + 15c = 12*100
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Modify for elimination:
8t  +  8c  =  840 
8t + 15c   = 1200
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Subtract and solve for "c":
7c = 360
c = 51.43 lbs (amt. of cashews needed)
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t = 105-c
t = 53.57 lbs (amt of trail mix needed)
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Cheers,
Stan H.
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