10/2.This reduces to 5, which is the appropriate pace for running. Option D is correct.
To solve this problem
The formula speed = distance / time can be applied.
The distance (10 miles) divided by the time (2 hours) in this instance determines Mary's running speed (Speed):
Running pace is = 10/2.
Reduce the fraction's complexity:
5 is the running speed.
Therefore, Mary's running speed is 5 miles per hour.