<PRE><B>Question 94528</B>
A 27 gallon solution contain 9 gallon acid and 18 gallon water.  How much water must be added to get 25% Acid?
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Starter Solution:
amt of solution = 27 gallons ; Amt of acid = 9 gallon
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Additional solution:
amt = x gallons ; Amt of acid = 0
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Mixture solution:
Amt = (27+x) gallons ; amt of acid = 0.25(27+x) = 6.75 + 0.25x gallons
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EQUATION:
acid + acid = acid
9 + 0 =  6.75 + 0.25x
0.25x = 2.25 gallons
x = 9 gallons (# of gallons of water that must be added)
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Cheers,
Stan H.</PRE>