SOLUTION: Joy is an instructional assistant in one of the college labs. She is on a very tight budget. She loves Jamaican Blue Mountain coffee, but it costs $18 a pound. She decides to blend

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Question 211328: Joy is an instructional assistant in one of the college labs. She is on a very tight budget. She loves Jamaican Blue Mountain coffee, but it costs $18 a pound. She decides to blend this with regular coffee beans that costs $2.37 a pound. If she spends $14.25 on 3 pounds of coffee, how many pounds of each did she purchase?
Round your answer to two decimal places.
She purchased______pounds of Jamaican Blue Mountain Coffee.
She purchased______ pounds of Regular Coffee.
i have no idea how to do this!!!!!
please help!
Found 2 solutions by stanbon, checkley77:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
She loves Jamaican Blue Mountain coffee, but it costs $18 a pound. She decides to blend this with regular coffee beans that costs $2.37 a pound. If she spends $14.25 on 3 pounds of coffee, how many pounds of each did she purchase?
Round your answer to two decimal places.
She purchased______pounds of Jamaican Blue Mountain Coffee.
She purchased______ pounds of Regular Coffee.
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Equation:
value + value = value
2.37x + 18(3-x) = 14.25*3
Multiply thru by 100 to get:
237x + 5400 - 1800x = 1425*3
1563x = 1125
x = 0.7198 lb (amount of $2.37 coffee in the mixture)
3-x = 3-(0.7198) = 2.28 lb (amount of Blue Mountain in the mix)
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Cheers,
Stan H.

Answer by checkley77(12844) About Me  (Show Source):
You can put this solution on YOUR website!
18x+2.37(3-x)=3*14.25
18x+7.11-2.37x=42.75
15.63x=42.75-7.11
15.63x=35.64
x=35.64/15.63
x=2.28 pounds of the $18 coffee is used.
3=2.28=.72 pounds of the $2.37 coffee is used.
Proof:
18*2.28+2.37*.72=3*14.25
41.04+1.7=42.75
42.75~42.75
She purchased 2.28 pounds of Jamaican Blue Mountain Coffee.
She purchased .72 pounds of Regular Coffee.