Question 722341
 How many liters of 70% acid solution must be mixed with 10% acid solution to get 480 L of a 60% acid solution
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Using 2 variables:
Quantity Eq::: x + y = 480 L
Acid Eq::::: 70x+10y = 60*480
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Modify for elimination:
70x + 70y = 70*480
70x + 10y = 60*480
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Subtract and solve for "y":
60y = 10*480
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y = 80 L (amt. of 10% solution needed)
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x = 400 L (amt. of 70% solution needed)
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Cheers,
Stan H.
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