<PRE><B>Question 410834</B>
Thirty-three pints of acid solution contain 3 pints of pure acid. Find the number of pints of pure acid that must be added to the 33 pints so that the resulting solution is 25% pure acid.
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Equation:
acid + acid = acid
3 + x = 0.25(33+x)
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Multiply thru by 100 to get:
300 + 100x = 25*33 + 25x
75x = 525
x = 11 pints (amt. of pure acid needed)
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Cheers,
Stan H.
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