Whenever we dilute, we want to keep the number of solid the same. We want to increase the number of solids. So this is our current situation. We have a three molar solution where the red dots are the solid, blue dots are the solid. We want to go from a three molar to a one molar solution. So we need to ask ourselves, how many more blue dots do we need to add to go from a three molar to a one molar?