Question

Darryl wants to add enough water to 8 gallons of a 10% bleach solution to make a 5% bleach solution. Which equation can he use to find x, the number of gallons of water he should add?

Answer 1

We have 8 gallons of 10% bleach.

How much water to add to make a 5% bleach solution?

Adding 8 gallons of water would make 16 gallons of 5% bleach.

Explanation:

Answer 2

0.80 = (x + 8)(0.05) is the equation.

Explanation:

Darryl has a solution of bleach with the concentration of 10%.

10% bleach solution means in 100 ml solution amount of bleach is 10 gm

Now Darryl wants to change the concentration of this solution to 5%, means he wants to add water so that amount of liquid will change but amount of bleach in grams will remain the same.

Amount of bleach in 8 gallons of 10% solution of bleach will be = (Volume)×(concentration) = 8(.10) gm

Let Darryl adds x gallons of water in 10% solution of bleach to make it 5% solution of bleach.

Amount of bleach in 5% solution of bleach = (x + 8)(0.05) gm

Now in both the concentrations of bleach solution amount of bleach will remain same.

So, 0.8 = (x + 8)(0.05) will be the equation from which he can find the value of x.