72.60% is what you get when you turn the fraction 53/73 into a percentage.
The fraction 53/73 shows that 53 parts are taken out of a total of 73 equal parts. When you look at it as a part of a whole, it is a little more than half but still well below three‑quarters.
Knowing the percentage makes it easy to compare this value with other numbers, like test scores or interest rates. It’s a handy way to see that 53/73 is roughly three‑quarters of a whole, just a bit lower.