Using the stated percentage, it is determined that it has a 0.877 = 87.7% chance of arriving on time.
The number of desired outcomes divided by the total number of outcomes yields a probability.
A percentage can be regarded as a probability over a big sample.
In this question, 87.7% of flights arrive on time in Atlanta, based on a significant number of flights. As a result, there is a 0.877 = 87.7% chance that it will arrive on time.
