Question 766553
<pre>
how much water should be mixed with 12ml of alcohol to obtain 12% alcohol solution


Ans:
Let the volume of water to be mixed be x ml
Total volume of the mixture = (x+12) ml

If this is to be 12% alcohol solution, that means that the *mixture* contains
12% of alcohol by volume.

We know that the mixture has 12 ml of alcohol.

So, we get the equation - 12/(x+12) = 12% or 12/100

{{{12/(x+12) = 12/100}}}

Simplifying

{{{1/(x+12) = 1/100}}}

Cross multiplying

{{{x + 12 = 100}}}

x = 88 ml

Need  to add 88 ml of water to make it a 12% alcohol solution.

:)
</pre>