20/82 as a percentage is 24.39%. This is the rounded value you get when you change the fraction into a percent.
The fraction 20/82 means you have 20 parts out of a total of 82 equal parts. It can be simplified a little, but the decimal and percent form stay the same after rounding.
In everyday situations, a value like 24.39% can show up in things like test scores, discount offers, or data reports. It tells you roughly one quarter of the whole.
Remember that the percentage gives a quick way to see the size of the part compared to the whole, without having to work with the original numbers.