10 divided by 66 is about 15.15% when written as a percentage.
The fraction 10/66 can be reduced to 5/33, which shows the same size in a simpler form. It represents a small portion of a whole, just a little more than one‑tenth.
You might see this percentage in a poll or a test score, where about fifteen out of every hundred people chose a certain option. It’s a handy way to understand how big or small a part of a group really is.