When you turn 21/81 into a percent, you get 25.93%. This is the rounded value you’d use in most everyday situations, and it tells you that 21 out of 81 parts is just a little over a quarter.
The fraction 21/81 can be reduced by dividing both the numerator and the denominator by 3, giving you the simpler form 7/27. Even in its reduced state, the value is still the same, so the percentage stays at 25.93%.
Knowing the percentage makes it easy to compare this amount with other numbers. For example, if you scored 21 points out of a possible 81 on a test, you earned roughly 25.93% of the total points—a clear, quick way to see how you did.
