The fraction 15/20 is equal to 75.00% when converted to a percentage. This means that 15 out of 20 parts represent three-quarters of the whole. It's a common fraction that comes up in various everyday situations, from test scores to statistics.
When we think about 75%, it's often associated with things being mostly complete or mostly full. For example, if a battery is at 75% charge, we know it's got plenty of power left. Or if 75% of people agree on something, that's a clear majority. The fraction 15/20 gives us this same sense of a substantial portion, whether we're talking about slices of pizza eaten or questions answered correctly on a quiz.