<PRE><B>Question 1033124</B>
A certain quantity was taken from a ten liter 30% alcohol solution and replaced by pure alcohol so as to produce 51% alcohol solution. How many liters were taken and replaced? 
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Equation:
alch - alch + alch = alch
0.30*10 - 0.30x + 1*x = 0.51*10
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30*10 - 30x + 100x = 51*10
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70x = 21*10
x = 3 liters (amt. to be removed and replaced)
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Cheers,
Stan H.
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