Question

How many liters of a 60% acid solution must be added to 14 liters of a 10% acid solution to produce a 25% acid solution?

Answer 1

i loathe word problems :)

Answer 2

x(.6) + 14(.1) = (x+14)(.25)
.6x + 1.4 = .25x + 3.5
.6x - .25x = 3.5 - 1.4
x(.6 - .25) = 2.1
x(.35) = 2.1
x= (2.1)/(.35) = 210/35
x = 6

Double check:

6(.6) + 14(.1) = 20(.25)
3.6 + 1.4 = 5

5=5 (its good) :)