Question 405455
A chemistry student mixes a 10% solution with a 20% solution to get 20L of a 13% solution. how much of each is used? 
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Equations
active + active = active
0.10x + 0.20(20-x) = 0.13*20
Multiply thru by 100 to get:
10x + 20*20 - 20x = 13*20
-10x = -7*20
x = (1/2)7
x = 3.5L (amt of 10% solution needed)
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20-x = 16.5L (amt of 20% solution)
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Cheers,
Stan H.
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