How many gallons of distilled water must be mixed with 50 gallons of 30% alcohol solution to obtain a 25% solution. distilled water is 0% alcohol ...?

Let P be the product solution, A be the 30% alcohol solution and W be the distilled water.

If we multiply the percentage of alcohol to the volume of the stream, we can obtain the amount of alcohol. Alcohol in the product is the sum of the alcohol in the solution and water.

Vp x 0.25 = 50 x 0.3 + Vw x 0

Vp = 60 gallons of product solution

Volume of product = volume of alcohol sol + vol of water

60 = 50 + Vw

Vw = 10 gallons

10 gallons of water must be added.