<PRE><B>Question 658692</B>
You have 18 milliliters of a 45% alcohol solution. How many milliliters of a 51% alcohol solution needs to be added to make a 49% alcohol solution? 
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Equation:
alcohol + alcohol = alcohol
0.45*18 + 0.51x = 0.49(18+x)
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Multiply thru by 100 to get:
45*18 + 51x = 49*18 + 49x
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2x = 4*18
x = 36 ml (amt of 51% solution to add)
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Cheers,
Stan H.
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