I need help in solving this word problem:
A corrupt barman attempts to prepare 100ml of some drink by mixing 30ml of ethanol with 70 ml of water. Does he succeed? If not, what volumes should have been mixed in order to arrive at a mixture of the same strength but of the required volume?
No, this isn't right because that is not how you make up a percent volume/volume solution.
Therefore, the way for him to have made a proper drink ...
This solution provides the correct description on how the barman should mix the volumes to arrive at a mixture of the same strength of the required volume. It also includes the definition of the proof rating for alcohol.