This question is a case of conditional probability and thus it can be solved by the use of the formula:

Now, in our case, let A be the event that a flight departs on schedule and let B be the event that a flight arrives on schedule.
Thus, from the given data, we know that:
and

Thus, the conditional probability that a flight that departs on schedule also arrives on schedule will be:

Therefore, when expressed as a percentage, rounded to two places of decimal, the required probability is 79.27%.