Question 265017
Each morning the manager mixes up 120 pounds of the special blend to sell to his customers. 
The coffee is a mixture of Columbian coffee selling for $5.00 per pound and Brazilian coffee selling for $8.00 per pound. 
The mixture sells for $7.00 per pound. 
How many pounds of Brazilian coffee is in the 120 pound mixture?
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Two equation solution:
Quantity Eq:::: c + b = 120 lbs.
Value Eq:::::: 5c +8b = 7*120
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Multiply thru the Quantity equation by 5 to get:
5c + 5b = 5*120
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Subtract that from the Value Eq and solve for "b":
3b = 2*120
b = 80 lbs (amount of Brazilian coffee in the mixture)
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Cheers,
Stan H.