<PRE><B>Question 793497</B>
a photographer wants to mix 3 liters of a 4% acetic acid solution with a 15% solution to get a 9% solution. How many liters of 15% solution should be used to obtain 9% solution?
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Equation::
acid + acid = acid
0.04*3 + 0.15x = 0.09(3+x)
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4*3 + 15x = 9*3 + 9x
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6x = 5*3
x = 2.5 liters (amt. of 15% solution needed)
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Cheers,
Stan H.
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