Question 1037557
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How many liters of water should be added to 3 liters of a 70 percent alcohol solution to obtain a 50 percent solution
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<pre>
{{{(3*0.7)/(3 + w)}}} = 0.5     ("alcohol percentage contents" equation)

3*0.7 = 0.5*(3 + w),

2.1 = 1.5 + 0.5w,

0.5w = 2.1 -1.5,

0.5w = 0.6   --->  w = {{{0.6/0.5}}} = 1.2.

<U>Answer</U>.  1.2 liters of water.
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