Question

How much water should be mixed with 12 ml of alcohol so as to obtain $12\%$ alcohol solution?

Answer 1

Let the volume of water to be mixed be x ml

Total volume of the mixture = (x+12) ml

If this is to be a 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

Simplifying

Cross multiplying

x = 88 ml

So w need to add 88 ml of water to make it a 12% alcohol solution