6/64 as a percentage is 9.38%. This number tells you how much of a whole the fraction represents when you look at it on a scale of 100.
The fraction 6/64 can also be simplified to 3/32, which still gives the same percentage. Seeing it as a percent makes it easy to compare with other values that are already expressed out of 100.
Whenever you need to talk about parts of a whole in everyday situations—like grades, discounts, or statistics—turning the fraction into a percent, such as 9.38%, lets people understand the size of the portion instantly.