How much water needs to be added to 0.5 l of a solution of alcohol in water so that the volumetric

How much water needs to be added to 0.5 l of a solution of alcohol in water so that the volumetric alcohol content in the solution decreases from 60% to 40%

Given:
Alcohol solution = 0.5l;
Alcohol content = 60%;
Amount of water to add =? L.
If alcohol in 0.5 liters of solution = 60% (0.5 / 10 * 6 = 0.3l (amount of alcohol in solution) 100% alcohol), then water = 40% (0.5 / 10 * 4 = 0.2l amount of water in solution) … From this it follows that every 0.1 l of water reduces the percentage of alcohol by 20%. In order to obtain a solution of alcohol with 40% alcohol, add 0.1 l of water.