How to find the part from the whole Practice Test

A pitcher is currently $\frac{4}{5}$ of the way full of water. If 3 ounces are poured out, then the pitcher would be of the way full. How many ounces of water are in the pitcher before the 3 ounces are poured out?

In the 30-day month of January, for every three days it snowed, there were seven days it did not snow. The number of days in January on which it did not snow was how much greater than the number of days in January on which it snowed?