Hello, thank you for taking the time to post your question!
The key on this type of question is to set up an equation that relates the values to one another. On this one we have
C1V1 = C2V2, meaning that
V2 = (C1V1/C2)
Plugging in the values that were given that becomes
V2 = (0.15*20) / 0.06 = 50
Meaning that the volume of the final solution needs to be 50 ounces.
That means the amount of water that needs to be added to the mixture is
50 oz – 20 oz = 30 oz of water
I hope that helps you get moving in a better direction on this type of question! Feel free to reach out if you have any additional questions beyond that :)
