13/20 = 65%
A value like 13/20, or 65%, might show up as a score on a quiz, a phone battery level, or the share of people who choose one option in a survey. It means a little under two-thirds of the whole.
To picture it quickly, imagine 20 equal pieces and shade 13 of them. You can also think of it as more than half, but not quite two-thirds.
One common mix-up is treating 65% as if it means 65 out of 20, rather than 65 out of 100. The fraction 13/20 describes the same share, just using a different-sized whole.