SOLUTION: A chemist has one solution that is 25% salt and another solution that is 10% salt. How many liters of each should the chemist use to make 120 liters of a solution that is 15% salt?

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Question 338649: A chemist has one solution that is 25% salt and another solution that is 10% salt. How many liters of each should the chemist use to make 120 liters of a solution that is 15% salt?
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website!
A chemist has one solution that is 25% salt and another solution that is 10% salt. How many liters of each should the chemist use to make 120 liters of a solution that is 15% salt?
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Equation:
salt + salt = salt
0.25x + 0.10(120-x) = 0.15*120
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Multiply thru by 100 to get:
25x + 10*120-10x = 15*120
15x = 5*120
x = 40 liters (amt. of 25% solution needed in the mixture)
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120-80 liters (amt. of 10% solution needed in the mixture)
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Cheers,
Stan H.
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Answer by Alan3354(69443) (Show Source):
You can put this solution on YOUR website!
Do it like this one.
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What quantity x of a 75% acid solution must be mixed with a 25% solution to produce 500 mL of a 40% solution?
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s = 75% acid volume
t = 25% acid volume
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s + t = 500
0.75s + 0.25t = 0.4*500 = 200 --> x4
3s + t = 800
1s + t = 500
-------------- Subtract
2s = 300
s = 150 ml of 75%
t = 350 ml of 25%