How much water should we add to 5 gallons of 18% acid solution to dilute it to a concentration of 10%?

We should add

gallons of water to dilute the concetration.

4 gallons of water is needed to dilute to a concentration of 10%.

Step-by-step explanation:

It is given that,

The 5 gallons of water contains 18% of acid solution.

Now, we are asked to find the gallons of water needed to dilute it to a concentration of 10% acid solution.

We obtain the equation by stating that the amount of acid 10% in the water must dilute up to 18%.

For this, x amount of water should be added.

Therefore, the equation is framed as,

⇒ 0.1 (x+5) = 5 (0.18)

⇒ 0.1x + 0.5 = 0.9

⇒ 0.1x = 0.9 - 0.5

⇒ x = 0.4 / 0.1

⇒ x = 4

∴ 4 gallons of water is needed to dilute to a concentration of 10%.