Answer:
I would think 3/5 a mile.
Step-by-step explanation:
If you can walk 1/5 mile in 1/3 hour a full hour would be 3/3 or 1
and it seems as if every 1/3 hour there is 1/5 mile so it would be 3/5 becuase of the fact that it is oen mile every 1/3 of hour and there are only thirds. So you can go as high as 3.
Sorry if i explained that horribly.