The FAA tracks average flight delays. It found that, last year, a particular airline had an average flight delay of 10 minutes. So far this year, the airline has averaged 28 minutes. What is the percent of increase in the average flight delay?

To calculate the percent increase in the average flight delay, we first need to find the difference between last year's average delay and this year's average delay, then divide that difference by last year's average delay and multiply by 100 to get the percentage.

Difference in average delay = 28 minutes - 10 minutes = 18 minutes

Percent increase = (18 minutes / 10 minutes) * 100 = 180%

Therefore, the percent increase in the average flight delay is 180%.