Question

Boris has 10 ounces of a 10% acid solution. How many ounces of 25% acid solution should he add to make a solution that is 20% acid?

Thank you.

Answer 1

10 oz pot has 1 oz acid and 9 oz water

x oz pot has .25 x oz acid and .75 x oz water

so

acid = 1 + .25 x
water = 9 + .75 x
total = 10 + x
and
(1 + .25 x) = .2 ( 10 + x)
1 + .25 x = 2 + .2 x
.05 x = 1
x = 20 oz

Answer 2

Thank you very much for all your great help! Once again, thank.

Answer 3

You are welcome :)