The fraction 18/99 is equal to 18.18% when converted to a percentage and rounded to the nearest two decimal places. This percentage represents how much of a whole the fraction represents. In other words, if you had 99 items and took 18 of them, you'd have about 18.18% of the total.
To put this in perspective, 18.18% is a little less than one-fifth of something. It's not a huge amount, but it's not tiny either. You might see percentages like this when talking about things like test scores, sales figures, or even in cooking recipes. For example, if 18.18% of a cake recipe is sugar, that means sugar makes up a noticeable part of the ingredients, but it's not the main component.