Question 354752
A dehydrated patient needs a 3.82% saline IV. Unfortunately, the hospital only has bags of 4% and 3% saline solutions. How many liters of each of these solutions should be mixed together to yield 5 liters of the desired concentration? 
So far I've come up with this: 
x= 4% solution; y= 3% solution
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Quantity Eq:::  x + y = 5 liters
Salt Eq::::::::4x + 3(5-x) = 3.82*5
4x + 15 -3x = 19.1
x = 4.1 liters (amt. of 4% solution needed in the mixture)
y = 5-4.1 = 0.9 liters (amt of 3% solution needed in the mixture)
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Cheers,
Stan H.
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