When you change the fraction 28/63 into a percent you get 44.44%. This is the rounded value you would use in most everyday situations.
The fraction 28/63 can be reduced to 4/9, which is a common simple fraction. Both 28/63 and 4/9 represent the same part of a whole, just expressed with different numbers.
Knowing that 28/63 is about 44.44% helps when you compare it to other percentages, like grades or discounts. It tells you that a little less than half of the whole is being considered.