66/76 as a percentage is 86.84%. This shows that the fraction is quite close to a whole, and the rounded value makes it easy to compare with other numbers.
The fraction 66/76 can be thought of as 66 parts out of a total of 76 equal parts. When you look at it this way, you can see it represents a large portion of the whole set, which is why the percentage is high.
Rounded to two decimal places, 86.84% is useful in everyday situations—like reporting test scores or measuring success rates—because it gives a clear and simple picture without too many digits.