64/78 as a percentage is 82.05%. This value shows how much of a whole the fraction represents when you think in terms of hundredths. It’s a quick way to see the size of the fraction at a glance.
The fraction 64/78 can also be reduced to its simplest form, 32/39, but the percentage stays the same. Whether you write it as a fraction or a percent, it still tells you the same amount of the whole.
Using the percentage makes it easier to compare with other numbers that are already in percent form. So whenever you need to talk about 64/78, you can simply say 82.05% and be understood.