18 liters of 14% bleach contains 0.14×18 = 2.52 liters of bleach.
Adding [tex]x[/tex] liters of pure water to the solution increases the total volume to [tex]18+x[/tex] liters without changing the total amount of bleach.
To end up with a 10% bleach solution, we must add
[tex]\dfrac{2.52}{18+x} = 0.10 \implies 2.52 = 1.8 + 0.10x \implies 0.10x = 0.72 \implies x=\boxed{7.2}[/tex]
liters of water.
