88/91 as a percentage is 96.70%. This fraction is just a little under one whole, so it shows up as a high percentage when you convert it.
The fraction 88/91 can be thought of as 88 parts out of a total of 91 equal parts. Because the numerator is close to the denominator, the value is close to 1, which explains why the percentage is so high.
When you see a percentage like 96.70%, it tells you that the amount is almost the entire whole. In everyday terms, that means you have about 97 out of every 100 units, which is a useful way to compare sizes quickly.
