SOLUTION: *Use a system of equations to solve (2 variables and 2 equations)*: In order to complete her science experiment, Merrie needs 20 liters of a solution which is 25% alcohol. The o

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Question 834308: *Use a system of equations to solve (2 variables and 2 equations)*:
In order to complete her science experiment, Merrie needs 20 liters of a solution which is 25% alcohol. The only two alcohol solutions available in the school laboratory are a solution which is 40% alcohol and another which is 15% alcohol. How many liters of each of these two solutions must she mix together to produce the required solution?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Use a system of equations to solve (2 variables and 2 equations)*:
In order to complete her science experiment, Merrie needs 20 liters of a solution which is 25% alcohol. The only two alcohol solutions available in the school laboratory are a solution which is 40% alcohol and another which is 15% alcohol. How many liters of each of these two solutions must she mix together to produce the required solution?
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Quantity: t + f = 20 liters
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Alcohol: 0.40t + 0.15f = 0.25*20
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Modify:
40t + 40f = 40*20
40t + 15f = 25*20
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Subtract and solve for "f":
25f = 300
f = 12 liters (amt. of 15% solution needed)
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t = 20-12 = 8 liters (amt. of 40% solution needed)
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Cheers,
Stan H.
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