Please I need help!! Jason has 4 gallons of hand sanitizer that contains 25% alcohol. He wants to make a hand sanitizer that contains 50% alcohol. How many gallons of pure alcohol should he add?

2 gallons

Step-by-step explanation:

25% of 4 gallons is 1 gallons, which means that 75% of the hand sanitizer is not alcohol, and is 3 gallons. since that is the amount of not alcohol, and we want it to be 50% solution, it has to be 3 gallons of alcohol in total, and 3-1=2.

step-by-step explanation:

the multiplicative inverse of a fraction a/b is b/a. for the multiplicative inverse of a real number, divide 1 by the number. for example, the reciprocal of 5 is one fifth 1/5 or 0.2, and the reciprocal of 0.25 is 1 divided by 0.25, or 4.