If the alcohol is absolute alcohol to make 1 gallon (4 quarts), then mix in 3 quarts water and 1 quart alcohol.
However, most of the time, alcohol comes in 96.5% alcohol, then we will define x=volume of alcohol in gal, then 1-x=volume of water, and solve following equation for x: 0.965x+(1-x)*0=0.25 x=0.25*0.965=0.259 gal will need 0.259 gal of 96.5% alcohol and 0.741 gal. of water.
