The fraction 81/99 is equal to 81.82% when converted to a percentage and rounded to two decimal places. This percentage represents how much of a whole the fraction represents. In other words, if you had 99 equal parts of something and took 81 of those parts, you'd have 81.82% of the whole.
To put this in perspective, 81.82% is pretty close to 82%, which is just over four-fifths of a whole. It's a fairly large percentage, more than three-quarters but less than nine-tenths. In everyday situations, you might see this percentage used in things like test scores, sales discounts, or statistics about various topics.