Question

The question is:
Jason has 20 gallons of a 12% alcohol solution. How many gallons, to the nearest tenth, must be replaced by a 36% alcohol solution to give 20% gallons of 15% alcohol solution.

I need and explanation on how to set it up and do it. I have a test today and I don’t understand it.

Answer 1

Answer:

2.5 gallons of the 20% solution must be replaced by the 36% solution.

Step-by-step explanation:

$.12(20 - x) + .36x = 20(.15)$

$2.4 - .12x + .36x = 3$

$2.4 - .24x = 3$

$- .24x = - .6$

$.24x = .6$

$x = 2.5$