SOLUTION: Please help me!!! I am not sure if I have set this up properly! a dehydrated patient needs a 3.24% saline IV. Unfortunately the hospital only has bags of 1% and 9% saline solutio

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Question 626844: Please help me!!! I am not sure if I have set this up properly!
a dehydrated patient needs a 3.24% saline IV. Unfortunately the hospital only has bags of 1% and 9% saline solutions. How many liters of each of these solutions should be mixed together to yield 5 liters of the desired concentration. This is what I have done please let me know if I've done it right or give me guidance to the right way.

x + y = 5; x = 5 - y
x + 9y = 5 x 3.24 = 16.2
5 - y + 9y = 16.2
8y = 11.2
y = 1.4 L of 9%
x = 3.6 L of 1%
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
dehydrated patient needs a 3.24% saline IV. Unfortunately the hospital only has bags of 1% and 9% saline solutions. How many liters of each of these solutions should be mixed together to yield 5 liters of the desired concentration.
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Equation:
salt + salt = salt
0.01x + 0.09(5-x) = 0.0324*5
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Multiply thru by 10000 to get:
100x + 900*5 - 900x = 324*5
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-800x = -576*5
x = 3.6 liters (amt. of 1% solution needed)
5-x = 1.4 liters (amt. of 9% solution needed)
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Congratulations; you have the correct answers.
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Cheers,
Stan H.
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