Answer:
His time would be least likely greater than 27.9 minutes or smaller than 21.5 minutes.
Explanation:
With an standard deviation of 3.2 minutes, it is clear that the maximum time taken by Roman to complete his run of 3 miles would be
Average time + standard deviation = 24.7 minutes + 3.2 minutes = 27.9 minutes
The minimum time taken by Roman to complete his run of 3 miles would be
Average time - standard deviation = 24.7 minutes - 3.2 minutes = 21.5 minutes
Hence, his time would be least likely greater than 27.9 minutes or smaller than 21.5 minutes.