To find the time of the person who came in second place, we first need to arrange the swimmers' times in ascending order:
- 69.15 seconds
- 69.28 seconds
- 74.5 seconds
- 75.4 seconds
The swimmer with the lowest time (69.15 seconds) came in first. Therefore, the time of the person who came in second place is 69.28 seconds.
So, the answer is 69.28 seconds.